Compound inhibiting dipeptidyl peptidase IV

ABSTRACT

A dipeptidyl peptidase IV inhibitor which is satisfactory in respect of activity, stability and safety and has an excellent action as a pharmaceutical agent. A compound represented by the following general formula or a pharmaceutically acceptable salt thereof: 
                         
wherein R 1  and R 2  each represents hydrogen, an optionally substituted C1-6 alkyl group, or —COOR 5  whereupon R 5  represents hydrogen or an optionally substituted C1-6 alkyl group, or R 1 , R 2 , and a carbon atom together represent a 3- to 6-membered cycloalkyl group, R 3  represents hydrogen or an optionally substituted C6-10 aryl group, R 4 represents a hydrogen or a cyano group, D represents —CONR 6 -, —CO— or —NR 6 CO—, R 6  represents hydrogen or an optionally substituted C1-6 alkyl group, E represents —(CH 2 ) m — whereupon m is 1 to 3, —CH 2 OCH 2 —, or —SCH 2 —, n is 0 to 3, and A represents an optionally substituted bicyclic heterocyclic group or bicyclic hydrocarbon group.

CROSS REFERENCE TO RELATED APPLICATION

This application is a National Phase of International Application No.PCT/JP2004/000886 having an international filing date of Jan. 30, 2004,published in Japanese on Aug. 12, 2004, which claims the benefit ofJapanese Application 2003-023077, filed Jan. 31, 2003, the entirety ofwhich is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a compound which has an excellentinhibitory effect on dipeptidyl peptidase IV (abbreviated hereinafter toDPP-IV) and is useful for treatment and prevention of type 2 diabetes,treatment or prevention of its related complications, or treatment ofother pathologic condition associated with DPP-IV, or pharmaceuticallyacceptable salts thereof.

BACKGROUND ART

DPP-IV is one kind of serine protease hydrolyzing a dipeptide Xaa-Pro orXaa-Ala (Xaa may be any amino acid) specifically from the N-end of apolypeptide chain. The role of DPP-IV (also called CD26) in vivo and therelationship of this enzyme with diseases are not completely elucidated,but there are many reports thereon. In particular, attention is paidrecently to the role of DPP-IV as an enzyme participating in theinactivation of glucagon-like peptide 1 (abbreviated hereinafter toGLP-1).

GLP-1 is a peptide hormone which without inducing insulin secretion byitself, has an action of increasing insulin secretion induced byglucose. Accordingly, its enhancement of insulin secretion depending onblood glucose level can be expected with less possibility ofhypoglycemia. Further, there is also a report suggesting that GLP-1 hasan appetite suppressing action. However, GLP-1 is rapidly cleaved byDPP-IV, so GLP-1 itself is hardly applicable as medicine. Accordingly,peptide analogues of GLP-1 have been examined, but any of such analoguesare injections, but are not preparations for oral administration.

Under these circumstances, inhibition of the cleavage enzyme DPP-IV wasanticipated in order to prevent the degradation of GLP-1 therebyenhancing the activity of GLP-1. This involves orally administering aDPP-IV inhibitor thereby keeping the concentration of GLP-1 intact invivo to prevent and treat diabetes and the like, particularly type 2diabetes, by the action of GLP-1. Such treatment method is also expectedto have an effect of preventing or treating other diseases induced ordeveloped by impaired glucose tolerance, for example, hyperglycemia(postprandial hyperglycemia), hyperinsulinemia, diabetic complications(renal diseases, neuropathy and the like), abnormal lipid metabolism,obesity and the like. Further, its effect on prevention or treatment ofdiseases expected to be ameliorated by enhancing the inhibition of foodintake of GLP-1, for example, bulimia, obesity and the like can also beexpected.

On the other hand, the reported action of DPP-IV further includescleavage of neuropeptides, activation of T cells, adhesion of metastatictumor cells to endothelium, and invasion of HIV virus into lymphocytes.It is found with respect to DPP-IV and known that the positiveness ofDPP-IV is increased in peripheral blood T cells from patients withrheumatism and the activity of DPP-IV is high in urine from patientswith nephritis. Accordingly, a substance inhibiting DPP-IV is expectedto have an effect of preventing or treating autoimmune diseases (forexample, arthritis, rheumatoid arthritis), osteoporosis, acquired immunedeficiency syndrome (AIDS), rejection of transplanted organs andtissues, and the like.

Patent applications relating to DPP-IV inhibitors have also been alreadyfiled. WO02/51836, WO01/96295, US20020193390, U.S. Pat. No. 6,011,155and Japanese Patent Application National Publication No. 9-509921disclose 2-cyanopyrrolidine derivatives, and WO97/40832 disclosesaminoacyl thiazolidide derivatives. In addition to the compound groupdescribed above, Annual Report in Medicinal Chemistry, Vol. 36, pp.191-200 (2001) reports peptide derivatives such as aminoacyl pyrrolididederivative, dipeptide phosphonate derivative, dipeptide boratederivative, tetrahydroisoquinoline derivative and cyclic peptidederivative, and non-peptide derivatives such as N-phenylphthalimidederivative, N-phenylhomophthalimide derivative and isoquinolinederivative.

DISCLOSURE OF THE INVENTION

Up to now, many DPP-IV inhibitors have been reported, but any compoundscannot be said to be sufficient in respect of inhibitory activity,stability and safety, and are not satisfactory as pharmaceuticalpreparations. Accordingly, there is demand for development of compoundswhich have a therapeutic or prophylactic effect attributable to aninhibitory action on DPP-IV and are sufficiently satisfactory aspharmaceutical agents.

In view of the circumstances described above, the present inventors madeearnest study for the purpose of development of novel DPP-IV inhibitors.As a result, the present inventors have found that a compoundrepresented by the general formula below having a suitably hydrophobicbicyclic ring, particularly a bicyclic heterocyclic group, in its sidechain has a potent inhibitory activity on DPP-IV, and have developed thecompound to further increase its stability, thus completing the presentinvention.

That is, the present invention provides a compound represented by thefollowing formula:

(wherein R¹ and R² are the same or different and each represents ahydrogen atom, an optionally substituted C1-6 alkyl group, or —COOR⁵whereupon R⁵ represents a hydrogen atom or an optionally substitutedC1-6 alkyl group, or R¹ and R², together with a carbon atom to whichthey are bound, represent a 3- to 6-membered cycloalkyl group,R³represents a hydrogen atom or an optionally substituted C6-10 arylgroup, R⁴ represents a hydrogen atom or a cyano group, D represents—CONR⁶—, —CO— or —NR⁶CO—, R⁶ represents a hydrogen atom or an optionallysubstituted C1-6 alkyl group, E represents —(CH₂)_(m)— whereupon m is aninteger of 1to 3, —CH₂OCH₂—, or —SCH₂—, n is an integer of 0 to 3, and Arepresents an optionally substituted bicyclic heterocyclic group orbicyclic hydrocarbon group), or a pharmaceutically acceptable saltthereof, and in this specification, such compound is referred tohereinafter as “the compound of the present invention”.

The present invention also provides a DPP-IV inhibitor comprising thecompound of the present invention as an active ingredient. The DPP-IVinhibitor serves as a prophylactic or therapeutic agent for diseaseswhose morbid state is expected to be ameliorated by inhibiting theactivity of DPP-IV, for example, diabetes (particularly type 2diabetes), diabetic complications and the like.

BEST MODE FOR CARRYING OUT THE INVENTION

The DPP-IV inhibitor of the present invention is described in moredetail below. The compound of the present invention is a compoundrepresented by the following formula:

(wherein R¹ and R²are the same or different and each represents ahydrogen atom, an optionally substituted C1-6 alkyl group, or—COOR⁵whereupon R⁵ represents a hydrogen atom or an optionallysubstituted C1-6 alkyl group, or R¹ and R², together with a carbon atomto which they are bound, represent a 3- to 6-membered cycloalkyl group,R³ represents a hydrogen atom or an optionally substituted C6-10 arylgroup, R⁴ represents a hydrogen atom or a cyano group, D represents—CONR⁶—, —CO— or —NR⁶CO—, R⁶ represents a hydrogen atom or an optionallysubstituted C1-6 alkyl group, E represents —(CH₂)_(m)— where upon m isan integer of 1 to 3, —CH₂OCH₂—, or —SCH₂—, n is an integer of 0 to 3,and A represents an optionally substituted bicyclic heterocyclic groupor bicyclic hydrocarbon group), or a pharmaceutically acceptable saltthereof. Hereinafter, each symbol used in this specification isdescribed in more detail.

The optionally substituted C1-6 alkyl group means that an arbitrary(throughout this specification, the term “arbitrary” refers not only toone atom or group but also to multiple atoms or groups) hydrogen atom ofthe C1-6alkyl group may be substituted with a halogen atom (for example,a fluorine, chlorine, bromine or iodine atom), an oxo group, a nitrogroup, a cyano group, a phenyl group, —OR¹⁴, —NR¹⁵R¹⁶, —OCOR¹⁷, NHCOR¹⁸,—NHS(O₂)R¹⁹ or —S (O₂) NR²⁰R²¹ wherein R¹⁴, R¹⁷, R¹⁸ and R¹⁹ eachrepresents a hydrogen atom, a C1-6 alkyl group, a phenyl group or abenzyl group, R¹⁵, R¹⁶, R²⁰ and R²¹ are the same or different and eachrepresents a hydrogen atom, a C1-6 alkyl group or a phenyl group, or R¹⁵and R¹⁶, or R²⁰ and R²¹, may be combined with each other to form a 3- to6-membered alicyclic ring. Specific examples of the C1-6 alkyl groupinclude linear, branched or cyclic alkyl groups such as methyl, ethyl,propyl, isopropyl, cyclopropyl, butyl, isobutyl, s-butyl, t-butyl,cyclobutyl, pentyl, isopentyl, neopentyl, t-pentyl, cyclopentyl, hexyl,cyclohexyl and the like. Among these groups, C1-3 alkyl groups arepreferable.

The optionally substituted C1-6 alkoxy group means that an arbitraryhydrogen atom of the C1-6 alkoxy group may be substituted with a halogenatom (for example, a fluorine, chlorine, bromine or iodine atom), an oxogroup, a nitro group, a cyano group, a phenyl group, —OR¹⁴, —NR¹⁵R¹⁶,—OCOR¹⁷, NHCOR¹⁸, —NHS(O₂)R¹⁹ or —S (O₂) NR²⁰R²¹ wherein R¹⁴, R¹⁵, R¹⁶,R¹⁷, R¹⁸, R¹⁹, R²⁰ and R²¹ have the same meaning as defined above.Specific examples of the C1-6 alkoxy group include linear, branched orcyclic alkoxy groups such as methoxy, ethoxy, propoxy, isopropoxy,cyclopropoxy, butoxy, isobutoxy, s-butoxy, t-butoxy, cyclobutoxy,pentyloxy, isopentyloxy, neopentyloxy, t-pentyloxy, cyclopentyloxy,hexyloxy, cyclohexyloxy and the like. Among these groups, C1-3 alkoxygroups are preferable.

The optionally substituted C6-10 aryl group means that an arbitraryhydrogen atom on the ring of the aryl group may be substituted with aC1-6alkyl group, a halogen atom (for example, a fluorine, chlorine,bromine or iodine atom), an oxo group, a nitro group, a cyano group, aphenyl group, —OR¹⁴, —NR¹⁵R¹⁶, —OCOR¹⁷, NHCOR¹⁸, —NHS(O₂)R¹⁹ or—S(O₂)NR²⁰R²¹ wherein R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, R²⁰ and R²¹ have thesame meaning as defined above. Preferable examples of the aryl groupinclude phenyl, naphthyl, and a bicyclic group (for example indanyl orthe like) having a 6-membered ring condensed with a 5-, 6- or 7-memberedring, at least one ring of which is an aromatic ring.

The optionally substituted bicyclic heterocyclic group means that anarbitrary hydrogen atom on the ring of the bicyclic heterocyclic groupmay be substituted with an optionally substituted C1-6 alkyl group, anoptionally substituted C1-6 alkoxy group, a halogen atom (for example, afluorine, chlorine, bromine or iodine atom), an oxo group, a nitrogroup, a cyano group, a phenyl group, —OR¹⁴, —NR¹⁵R¹⁶, —OCOR¹⁷, NHCOR¹⁸,—NHS(O₂) R¹⁹ or —S(O₂)NR²⁰OR²¹ wherein R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, R²⁰and R²¹ have the same meaning as defined above. Preferable examples ofthe bicyclic heterocyclic group include a bicyclic heterocyclic grouphaving a 6-membered ring having carbons and 1 to 4 heteroatoms (oxygen,nitrogen, sulfur atom) condensed with a 5-, 6- or 7-membered ring,particularly, a benz derivative, pyridyl derivative and pyrimidylderivative. Examples thereof include indolyl, benzothiazolyl,benzoimidazolyl, benzoxazolyl, pyrazolopyridinyl, imidazopyridinyl,pyrazolopyrimidinyl, triazolopyrimidinyl, benzotriazolyl, benzofuranyl,isobenzofuranyl, benzothiophenyl, benzisoxazolyl, benzoisothiazolyl,triazolopyrimidinyl, quinolinyl, isoquinolinyl, cinnolinyl, chromenyl,pyridopyrimidinyl, quinazolinyl, quinoxalinyl, naphthyridinyl,thianaphthenyl, isothianaphthenyl, dihydroindolyl, dihydroisoindolyl,dihydropurinyl, dihydrothiazolopyrimidinyl, dihydrobenzodioxanyl,isoindolinyl, indazolyl, pyrrolopyridinyl, tetrahydroquinolinyl,decahydroquinolinyl, tetrahydroisoquinolinyl, decahydroisoquinolinyl,tetrahydronaphthyridinyl, tetrahydropyridoazepinyl and the like.

The optionally substituted bicyclic hydrocarbon group means that anarbitrary hydrogen atom on the bicyclic hydrocarbon group may besubstituted with the same substituent group as on the above-mentionedbicyclic heterocyclic ring. Examples thereof include pentalenyl,indanyl, indenyl, naphthalenyl, tetrahydrobenzocycloheptenyl,tetrahydronaphthalenyl and the like.

Among the compounds of the present invention, particularly preferablecompounds are described below in more detail.

In respect of stability, the compound is preferably a compound whereinR¹ and R² are preferably C1-6 alkyl groups, more preferably C1-3 alkylgroups, particularly methyl groups. R³ is preferably a hydrogen atom,and for inhibitory action on DPP-IV, R⁴is preferably a cyano group.Further, A is preferably an optionally substituted 6-5, 6-6 or6-7-system bicyclic heterocyclic group containing at least oneheteroatom out of nitrogen, oxygen and sulfur atoms, particularlypreferably an optionally substituted 6-5-system bicyclic heterocyclicgroup containing 1 to 3 nitrogen atoms. In addition, D is preferably—CONH— or —CO—, E is preferably —CH₂CH₂—, and n is preferably 1 or 2.

In the preferable compounds of the general formula (I), particularlypreferable bicyclic heterocyclic groups represented by A are describedin more detail below.

One group is the case where D in the general formula (I) is —CO—, and Ais a 6-5-system bicyclic alicyclic heterocyclic group represented by thefollowing formula:

wherein x is an integer of 0 to 2, R⁷, R⁸, R⁹ and R¹⁰ are the same ordifferent and each represents a hydrogen atom, a halogen atom, a hydroxygroup, a trifluoromethyl group, an optionally substituted C1-6 alkylgroup or an optionally substituted C1-6 alkoxy group. Particularly, thecompound wherein x is 1, that is, dihydroisoindole is preferable inrespect of activity, absorptivity, safety, and compound stability.

Another group is the case where D in the general formula (I) is —CONH—,and A is a 6-5-system bicyclic heterocyclic group represented by thefollowing formula:

wherein

represents a single or double bond, at least one of y, z, v and w is anoxygen, nitrogen or sulfur atom, R¹¹, R¹² and R¹³ may be substituted onany hydrogen atoms on the ring, are the same or different and eachrepresents a hydrogen atom, a hydroxy group, a trifluoromethyl group, atrifluoroacetyl group, an oxo group, an optionally substituted C1-6alkyl group, an optionally substituted C1-6 alkoxy group, or anoptionally substituted C6-10 aryl group. Particularly preferable is thecompound wherein 1 to 3 groups out of y, z, v and w are nitrogen atoms,and the remainder is a carbon atom. Further, the compound wherein y is anitrogen atom while the remainder are carbon atoms, or v, w and y arenitrogen atoms while z is a carbon atom, that is, indole orpyrazolopyrimidine is generally considered to be more preferable inrespect of activity, selectivity for the enzyme, ADME profile(absorptivity, metabolic stability, effect durability and the like),safety (mutagenicity, metabolic enzyme induction, metabolic enzymeinhibition, safety for each organ, and the like), compound stability,and the like.

The process for producing the compound of the present invention isdescribed by reference to the following reaction schemes (1 to 3).

wherein the compound represented by the general formula (IV-1) is thecompound wherein one hydrogen atom on the ring A was substituted withCOOH, and the other symbols have the same meaning as defined above.

The reaction scheme 1 is a step of obtaining a compound represented bythe general formula (I-1) by reacting a compound represented by thegeneral formula (IV-1) with a compound represented by the generalformula (V) or a salt thereof. Examples of the salt of the compoundrepresented by the general formula (V) include hydrochloride,trifluoroacetate and the like.

The reaction of the compound represented by the general formula (IV-1)with the compound represented by the general formula (V) or a saltthereof proceeds preferably under the temperature conditions of −10 to80° C., particularly, 0° C. to room temperature for 0.5 hour to 3 daysby using a condensation reagent (for example, dicyclohexylcarbodiimide,N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide or its hydrochloride,N,N′-carbonyldiimidazole or the like) activating the carboxylic acid ofthe compound represented by the general formula (IV-1) alone or incombination with an additive (N-hydroxysuccinimide, hydroxybenzotriazoleor the like) in the presence or absence of a base (for example,triethylamine, 4-dimethylaminopyridine or the like) in a suitablesolvent (for example, tetrahydrofuran, dichloromethane,N,N-dimethylformamide or the like).

wherein X represents a halogen atom, and the other symbols have the samemeaning as defined above.

The reaction scheme 2 is a step of obtaining a compound represented bythe general formula (I) by reacting a compound represented by thegeneral formula (VI) or a salt thereof with a compound represented bythe general formula (VII). Examples of the salt of the compoundrepresented by the general formula (VI) include hydrochloride,trifluoroacetate and the like.

The reaction of the compound represented by the general formula (VI)or-a salt thereof with the compound represented by the general formula(VII) proceeds preferably under the temperature conditions of −10 to 80°C., particularly, 0° C. to room temperature for 0.5 hour to 3 days inthe presence or absence of a base (for example, triethylamine,4-dimethylaminopyridine, potassium carbonate or the like) and anadditive (for example, sodium bromide, sodium iodide, potassium iodide)in a suitable solvent (for example, tetrahydrofuran, dichloromethane,N,N-dimethylformamide, acetone or the like).

wherein G is a protecting group for amino acid (for example,t-butoxycarbonyl (Boc)), and the other symbols have the same meaning asdefined above.

The reaction scheme 3 is a step of obtaining a compound represented bythe general formula (I) by deprotecting a compound obtained by reactinga compound represented by the general formula (VIII) with a compoundrepresented by the general formula (IX) or a salt thereof. Examples ofthe salt of the compound represented by the general formula (IX) includehydrochloride, trifluoroacetate and the like.

The amidation reaction proceeds preferably under the temperatureconditions of −10 to 80° C., particularly, 0° C. to room temperature for0.5 hour to 3 days by using a condensation reagent (for example,dicyclohexylcarbodiimide, N-(3-dimethylaminopropyl)-N′-ethylcarbodiimideor its hydrochloride, N,N′-carbonyldiimidazole or the like) activatingthe carboxylic acid of the compound represented by the general formula(VIII) alone or in combination with an additive (N-hydroxysuccinimide,hydroxybenzotriazole or the like) in the presence or absence of a base(for example, triethylamine, 4-dimethylaminopyridine or the like) in asuitable solvent (for example, tetrahydrofuran, dichloromethane,N,N-dimethylformamide or the like).

When the protecting group is for example a Boc group, the deprotectionreaction proceeds preferably under the temperature conditions of −10 to50° C., particularly, 0° C. to room temperature for 10 minutes to 24hours by using an acid such as hydrogen chloride or trifluoroacetic acidin a suitable solvent (for example, 1,4-dioxane, tetrahydrofuran or thelike).

Now, the process for producing the starting materials are described byreference to the following reaction schemes (4 to 7).

wherein each symbol has the same meaning as defined above.

The reaction scheme 4 is a step of obtaining the compound (V) byreacting a compound represented by the general formula (X) with acompound represented by the general formula (VII) and then deprotectingthe product.

The reaction of the compound represented by the general formula (X) withthe compound represented by the general formula (VII) proceedspreferably under the temperature conditions of −10 to 80° C.,particularly, 0° C. to room temperature for 0.5 hour to 3 days in thepresence or absence of a base (for example, triethylamine,4-dimethylaminopyridine, potassiumcarbonate or the like) and an additive(for example, sodium bromide, sodium iodide, or potassium iodide) in asuitable solvent (for example, tetrahydrofuran, dichloromethane,N,N-dimethylformamide, acetone or the like).

When the protecting group is for example a Boc group, the deprotectionreaction proceeds preferably under the temperature conditions of −10 to50° C., particularly, 0° C. to room temperature for 10 minutes to 24hours by using an acid such as hydrogen chloride or trifluoroacetic acidin a suitable solvent (for example, 1,4-dioxane, tetrahydrofuran or thelike).

wherein G¹ represents a protecting group for amino acid (for example,t-butoxycarbonyl (Boc)) or a hydrogen atom; R²² represents —COOH, —NH₂,or —NH— in the ring when A represents the general formula (II); R²³represents —COOH or —NH₂; one of R²² and R²³ represents a carboxylicacid, and the other represents an amine; and the other symbols have thesame meaning as defined above.

The reaction scheme 5 is a step of obtaining a compound represented bythe general formula (VI) by reacting a compound represented by thegeneral formula (IV-2) or a salt thereof (in the case of amine) with acompound represented by the general formula (XI) or a salt thereof (inthe case of amine) (followed by deprotection reaction when G¹ is aprotecting group for amino acid). Examples of the salt of the compoundrepresented by the general formula (IV-2) or (XI) include hydrochloride,trifluoroacetate and the like.

The amidation reaction proceeds preferably under the temperatureconditions of −10 to 80° C., particularly, 0° C. to room temperature for0.5 hour to 3 days, by using a condensation reagent (for example,dicyclohexylcarbodiimide, N-(3-dimethylaminopropyl)-N′-ethylcarbodiimideor its hydrochloride, N,N′-carbonyldiimidazole or the like) activatingthe carboxylic acid alone or in combination with an additive(N-hydroxysuccinimide, hydroxybenzotriazole or the like) in the presenceor absence of a base (for example, triethylamine,4-dimethylaminopyridine or the like) in a suitable solvent (for example,tetrahydrofuran, dichloromethane, N,N-dimethylformamide or the like).

When the compound represented by the general formula (IV-2) is acarboxylic acid (R²² is —COOH), the carboxylic acid can also be reactedas follows. That is, the carboxylic acid is converted into thecorresponding acid chloride (R²² is converted into —COCl) by usingoxalyl chloride, thionyl chloride or the like in a suitable solvent (forexample, tetrahydrofuran, dichloromethane, N,N-dimethylformamide or thelike), and the reaction with the compound represented by the generalformula (XI) (R²³ is —NH₂) or a salt thereof proceeds preferably underthe temperature conditions of −10 to 80° C., particularly, 0° C. to roomtemperature for 0.5 hour to 3 days in the presence or absence of a base(for example, triethylamine, 4-dimethylaminopyridine or the like).

When G₁ is, for example, a Boc group, the deprotection reaction proceedspreferably under the temperature conditions of −10 to 50° C.,particularly, 0° C. to room temperature for 10 minutes to 24 hours byusing an acid such as hydrogen chloride or trifluoroacetic acid in asuitable solvent (for example, 1,4-dioxane, tetrahydrofuran or thelike).

wherein J represents —OH or a halogen atom, and the other symbols havethe same meaning as defined above.

The reaction scheme 6 is a step of obtaining a compound represented bythe general formula (VII) by reacting a compound represented by thegeneral formula (XII) with a compound represented by the general formula(IX) and a salt thereof.

The compound represented by the general formula (XII) (after conversioninto the corresponding acid chloride by use of oxalyl chloride, thionylchloride or the like when J is —OH) is reacted with the compoundrepresented by the general formula (IX) or a salt thereof under thetemperature conditions of −10 to 80° C., particularly, 0° C. to roomtemperature for 0.5 hour to 3 days in the presence or absence of a base(for example, triethylamine, 4-dimethylaminopyridine or the like) in asuitable solvent (for example, tetrahydrofuran, dichloromethane,N,N-dimethylformamide or the like), whereby the compound represented bythe general formula (VII) is obtained.

wherein R²⁴ represents —NH₂, or when A represents the general formula(II), R²⁴ represents —NH— in the ring, and the other symbols have thesame meaning as defined above.

The reaction scheme 7 is a step of obtaining a compound represented bythe general formula (VIII) by reacting a compound represented by thegeneral formula (XIII) with a compound represented by the generalformula (IV-3) and a salt thereof.

The reaction proceeds preferably under the temperature conditions of −10to 80° C., particularly, 0° C. to room temperature for 0.5 hour to 3days, by using a condensation reagent (for example,dicyclohexylcarbodiimide, N-(3-dimethylaminopropyl)-N′-ethylcarbodiimideor its hydrochloride, N,N′-carbonyldiimidazole or the like) activatingthe carboxylic acid alone or in combination with an additive(N-hydroxysuccinimide, hydroxybenzotriazole or the like) in the presenceor absence of a base (for example, triethylamine,4-dimethylaminopyridine or the like) in a suitable solvent (for example,tetrahydrofuran, dichloromethane, N,N-dimethylformamide or the like).

The objective compound obtained in each of the steps described above canbe easily isolated by usual separation and purification method. As theisolation method, various kinds of generally used method can be used,and such method can be exemplified by recrystallization,reprecipitation, solvent extraction, column chromatography and the like.

The compound of the present invention can exhibit polymorphism, and canoccur multiple tautomers. Accordingly, the present invention encompassesany stereoisomers, optical isomers, polymorphs, tautomers, and arbitrarymixtures thereof.

The compound of the present invention includes pharmaceuticallyacceptable salts thereof. Examples of the pharmaceutically acceptablesalts include inorganic acid addition salts (for example, salts withhydrochloric acid, hydrobromic acid, hydriodic acid, sulfuric acid,nitric acid, phosphoric acid and the like), organic acid addition salts(for example, salts with methane sulfonic acid, benzene sulfonic acid,p-toluenesulfonic acid, formic acid, acetic acid, trifluoroacetic acid,oxalic acid, citric acid, malonic acid, fumaric acid, glutaric acid,adipic acid, maleic acid, tartaric acid, succinic acid, mandelic acid,malic acid, pantothenic acid, methylsulfuric acid and the like), saltswith an amino acid (for example, salts such as glutamic acid, asparticacid and the like) and the like. The reaction of forming the acidaddition salt can be carried out according to a conventional method.

The compound of the present invention can be provided as DPP-IVinhibitor. That is, the compound of the present invention exhibits apotent inhibitory action on DPP-IV, and is useful for prevention andtreatment of diseases curable by an inhibitory action on DPP-IV, forexample, diabetes (particularly type 2 diabetes), its relatedcomplications, obesity, autoimmune diseases (for example, arthritis,rheumatoid arthritis), osteoporosis, acquired immune deficiency syndrome(AIDS), rejection of transplanted organs and tissues, and the like.

Depending on the object, the method of administering the compound of thepresent invention can be selected from various administration formsdescribed in general rules for pharmaceutical preparations in theJapanese Pharmacopoeia. In particular, the compound of the presentinvention is formed preferably into a pharmaceutical preparation fororal administration. For forming the compound in the form of tablets fororal administration, orally ingestible ingredients used in the field maybe usually selected. Examples of such ingredients include excipientssuch as lactose, crystalline cellulose, white sugar and potassiumphosphate. If necessary, various additives usually used in the filed ofpharmaceutical manufacturing, such as a binder, a disintegrating agent,a lubricant and an aggregation inhibitor may be blended.

The amount of the compound of the present invention to be contained inthe preparation of the present invention, that is, in the pharmaceuticalcomposition of the present invention is not particularly limited and canbe suitably selected from a broad range. The amount of the compound ofthe present invention as an active ingredient is selected suitablydepending on the way of using it, the age, sex and other conditions ofthe patient, and the severeness of the disease, but usually the amountof the compound of the present invention is considered to be about 0.01to 500 mg per kg of body weight. The preparation of the presentinvention can be administered all at once or in 2 to 4 divided portionsper day.

Hereinafter, the present invention is described in more detail byreference to the Examples and Intermediate Examples, but these examplesare not intended to limit the present invention.

INTERMEDIATE EXAMPLE 1

(S)-1-(2-Chloroacetyl)pyrrolidine-2-carbonitrile

In a similar procedure as employed in a patent (WO98/19998), L-prolineamide (10.0 g) was reacted with chloroacetyl chloride (7.0 ml) and thensubjected to dehydration reaction to give the title compound (7.7 g,yield (Y.:51%).

¹H NMR; (DMSO-d₆) δ (ppm):2.0-2.2 (4H, m), 3.4-3.5 (1H, m), 3.6-3.7 (1H,m), 4.4-4.5 (2H, m), 4.78 (1H, q).

ESI/MS (m/z):173 (M+H)⁺, 171 (M−H)⁻.

INTERMEDIATE EXAMPLE 2

(R)-1-(2-Chloroacetyl)pyrrolidine-2-carbonitrile

In a similar procedure as employed in the Intermediate Example 1,D-proline amide (3.2 g) was reacted with chloroacetyl chloride (2.5 ml)and then subjected to dehydration reaction to give the title compound(3.2 g, Y.:66%).

¹H NMR; (DMSO-d₆) δ (ppm):2.1-2.4 (4H, m), 3.5-3.8 (2H, m), 4.0-4.2 (2H,m), 4.7-4.9 (1H, m).

ESI/MS (m/z):173 (M+H)⁺.

INTERMEDIATED EXAMPLE 3

(S)-3-(2-Chloroacetyl)thiazolidine-4carbonitrile

3-t-Butyl thiazolidine-3,4-dicarboxylate (2.0 g) was dissolved intetrahydrofuran (10 ml), and N,N′-carbonyl diimidazole (1.4 g) was addedthereto with ice-cooling. The mixture was warmed to room temperature andstirred for 6 hours. 1,4-Dioxane (10 ml) was added thereto, and themixture was added dropwise to 28% ammonia water (40 ml) cooled on an icebath. The mixture was warmed to room temperature and stirred for 20hours. The reaction solution was extracted with ethyl acetate (60 ml).The organic phase was washed with a saturated saline solution and driedover sodium sulfate anhydrous. The product was concentrated underreduced pressure to give t-butyl 4-carbamoylthiazolidine-3-carboxylate(1.6 g, Y.:81%).

4 N HCl/1,4-dioxane (3.5 ml) was added to the t-butyl 4-carbamoylthiazolidine-3-carboxylate (1.62 g) obtained above, and the mixture wasstirred overnight. The reaction mixture was neutralized (pH 7.5 to 8) byadding water and 10% sodium bicarbonate solution and concentrated underreduced pressure. N,N-Dimethylformamide was added thereto, then themixture was sonicated, and insolubles were removed by filtration. Thefiltrate was concentrated under reduced pressure to givethiazolidine-4-carboxylic acid amide (735 mg, Y.:80%).

In a similar procedure as employed in the Intermediate Example 1, thethiazolidine-4-carboxylic acid amide (102 mg) obtained above was reactedwith chloroacetyl chloride (105 mg) and then subjected to dehydrationreaction to give the title compound (87 mg, Y.:59%).

ESI/MS (m/z):191 (M+H)⁺.

INTERMEDIATE EXAMPLE 4

(S)-1-(2-Chloroacetyl)azetidine-2-carbonitrile

4 N HCl/1,4-dioxane (2.5 ml) was added to a solution of t-butyl2-carbamoylazetidine-1-carboxylate (500 mg) in 1,4-dioxane (2.0 ml)under cooling on an ice bath. The mixture was stirred for 2 hours atroom temperature. The reaction mixture was neutralized by adding 5 Nsodium hydroxide dropwise. The reaction mixture was concentrated underreduced pressure, then N,N-dimethylformamide was added thereto,insolubles were removed by filtration, and the filtrate was concentratedunder reduced pressure to give azetidine-2-carboxylic acid amide (161mg, Y.:65%).

In a similar procedure as employed in the Intermediate Example 1, theazetidine-2-carboxylic acid amide (161 mg) obtained above was reactedwith chloroacetyl chloride (200 mg) and then subjected to dehydrationreaction to give the title compound (112 mg, Y.:44%).

ESI/MS (m/z):159 (M+H)⁺.

INTERMEDIATE EXAMPLE 5

(S)-1-(2-Bromo-2-phenylacetyl)pyrrolidine-2-carbonitrile

2-Bromo-2-phenylacetic acid (500 mg) was dissolved in dichloromethane(30 ml), and oxalyl chloride (950 μl) and N,N-dimethylformamide (2drops) were added thereto and stirred at room temperature for 1 hour.The reaction solution was concentrated under reduced pressure, thendiluted with dichloromethane (20 ml), added dropwise to a solution of(S)-pyrrolidine-2-carbonitrile (310 mg) in triethylamine (650 μl) anddichloromethane (30 ml), and stirred at room temperature for 3 hours.10% Citric acid solution was added thereto, and the organic phase wasseparated, then washed with 4% sodium bicarbonate solution and asaturated saline solution, and dried over sodium sulfate anhydrous. Theproduct was concentrated under reduced pressure to give the titlecompound (700 mg, Y.: quant.).

ESI/MS (m/z):294 (M+H)⁺, 292 (M−H)⁻.

In a similar procedure as employed in the Intermediate Examples 1 to 5,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in Table 1. (Each symbolhas the same meaning as defined above.)

TABLE 1 Intermediate Example Compound Name ESI/MS(m/z) 63-(2-chloroacetyl)thiazolidine 166 (M + H)⁺ 164 (M − H)⁻ 71-(2-chloroacetyl)pyrrolidine 148 (M + H)⁺ 146 (M − H)⁻ 81-(2-chloroacetyl)piperazine-2- 187 (M + H)⁺ carbonitrile 185 (M − H)⁻164 (M + H)⁺ 9 1-(2-chloroacetyl)morpholine 162 (M − H)⁻

INTERMEDIATE EXAMPLE 10

(S)-Pyrrolidine-2-carbonitrile

L-Proline amide (23 g) was dissolved in tetrahydrofuran (1200 ml), thentriethylamine (22 g) was added thereto, and the mixture was cooled on anice bath. 2-Nitrophenylsulfonyl chloride (42 g) was added thereto andstirred for 1 hour at room temperature. Ethyl acetate and water wereadded thereto, and the organic phase was separated and dried over sodiumsulfate anhydrous. The product was concentrated under reduced pressure,then ether was added to the residue, and precipitated crystals werecollected by filtration and dried under reduced pressure. The resultingcrystals (45 g) were dissolved in pyridine (890 ml), and imidazole (23g) was added thereto and cooled on an ice bath. Phosphoryl chloride (31ml) was added dropwise thereto and stirred at room temperature for 2hours. Ice (1000 g) and ether (2000 ml) were added thereto, and theorganic phase was separated, washed with water and dried over sodiumsulfate anhydrous. The product was concentrated under reduced pressure,the resulting residue was dissolved in ether (4.1L), and filtered. 4 NHCl/1,4-dioxane (130 ml) was added dropwise to the filtrate with icecooling and stirred for 3 hours at room temperature. Precipitatedcrystals were collected by filtration and washed with ether. Thecrystals were dried under reduced pressure to give a hydrochloride (20g, Y.:88%) of the title compound as pale yellow crystals.

¹HNMR; (CDCl₃) δ (ppm):2.2-2.3 (2H, m), 2.3-2.4 (1H, m), 2.5-2.6 (1H,m), 3.5-3.7 (2H, m), 5.0 (1H, t).

INTERMEDIATE EXAMPLE 11

Piperidine-2-carbonitrile

In a similar procedure as employed in the Intermediate Examples 3 and10, a hydrochloride (4.4 g, Y.:69%) of the title compound was obtainedfrom piperidine-2-carboxylic acid (15 g).

ESI/MS (m/z):111 (M+H)⁺.

INTERMEDIATE EXAMPLE 12

(S)-1-[(2-Amino-1,1-dimethylethyl)aminoacetyl]pyrrolidine-2-carbonitriledihydrochloride

2-Methylpropane-1,2-diamine (5.0 g) was dissolved in dichloromethane(200 ml) and stirred for 15 minutes at 0° C. A solution of BOC-ON (15 g)in dichloromethane (60 ml) was added dropwise thereto and then stirredfor 2 hours at room temperature. The reaction mixture was diluted withchloroform with ice cooling and then acidified by 10% citric acidsolution, and the organic phase was separated. The aqueous phase wasalkalinized by 5 N sodium hydroxide solution, then extracted with ethylacetate, and the extract was dried over sodium sulfate anhydrous. Theproduct was concentrated under reduced pressure to give t-butyl(2-amino-2-methyl-1-propyl)carbamate (7.9 g, Y.:74%).

¹H NMR; (DMSO-d₆) δ (ppm):0.9 (6H, s), 1.4 (9H, s), 2.8 (2H, d), 6.7(1H, brt).

The t-butyl (2-amino-2-methyl-1-propyl)carbamate (7.9 g) obtained above,sodium iodide (8.7 g), and potassium carbonate (8.0 g) were suspended inacetone (230 ml). A solution of(S)-1-(2-Chloroacetyl)pyrrolidine-2-carbonitrile (10 g) in acetone (80ml) was added thereto with ice cooling, and stirred as such for 30minutes. The reaction mixture was stirred for 15 hours at roomtemperature and then concentrated under reduced pressure. The residuewas dissolved in chloroform, then insolubles were removed by filtration,and the filtrate was concentrated under reduced pressure. The resultingresidue was purified by colunm chromatography (eluting solvent;dichloromethane:methanol 80:1→60:1→40: 1) to give t-butyl(S)-{2-[(2-cyanopyrrolidine-1-yl)-2-oxoethylamino]-2-methyl-1-propyl}carbamate (12 g, Y.:91%).

¹H NMR; (DMSO-d₆) δ (ppm):0.9 (6H, s), 1.4 (9H, s), 1.9-2.2 (4H, m), 2.9(2H, d), 3.2-3.5 (4H, m), 3.5-3.7 (1H, m), 4.7-4.8 (1H, m), 6.6-6.7 (1H,brt).

ESI/MS (m/z):325 (M+H)⁺, 323 (M−H)⁻.

The t-butyl(S)-{2-[(2-cyanopyrrolidine-1-yl)-2-oxoethylamino]-2-methyl-1-propyl}carbamate(4.8 g) obtained above was dissolved in dichloromethane (50 ml). 4 NHCl/1,4-dioxane (50 ml) was added thereto under cooling on ice andstirred for 1 hour at room temperature. The product was concentratedunder reduced pressure to give the title compound (4.2 g, Y.:96%).

¹H NMR; (DMSO-d₆) δ (ppm):1.4 (6H, s), 2.0-2.3 (4H, m), 3.2 (2H, brs),3.5-3.6 (2H, m), 3.7-3.8 (1H, m), 4.0-4.2 (2H, m), 4.9 (1H, q), 8.5 (2H,brs), 9.4 (1H, brs), 9.5 (1H, brs)

ESI/MS (m/z):225 (M+H)⁺.

INTERMEDIATE EXAMPLE 13

(S)-1-[2-(1,1-Dimethyl-2-methylaminoethylamino)acetyl]-pyrrolidine-2-carbonitrile

(S)-1-[(2-Amino-1,1-dimethylethyl)aminoacetyl]-pyrrolidine-2-carbonitriledihydrochloride (1.48 g) was dissolved in acetonitrile (50 ml), and4-nitrophenyl formate (1.00 g) and potassium carbonate (1.37 g) wereadded thereto and stirred for 16 hours at room temperature. The reactionmixture was concentrated under reduced pressure, and the residue waspurified by column chromatography (eluting solvent;dichloromethane:methanol 5:1) to give(S)-N-{2-[2-(2-cyanopyrrolidin-1-yl)-2-oxoethylamino]-2-methyl-1-propyl}-formamide(693 mg, Y.:55%).

ESI/MS (m/z):253 (M+H)⁺.

The(S)-N-{2-[2-(2-cyanopyrrolidin-1-yl)-2-oxoethylamino]-2-methyl-1-propyl}formamide(690 mg) obtained above was dissolved in MeOH (30 ml). Sodiumcyanoborohydride (172 mg) was added there to and stirred for 6 hours atroom temperature. The reaction mixture was concentrated under reducedpressure, and the residue was purified by column chromatography (elutingsolvent; dichloromethane:methanol 5:1→3:1) to give the title compound(455 mg, Y.:70%).

¹H NMR; (DMSO-d₆) δ (ppm):1.4 (6H, s), 2.0 (2H, brs), 2.0-2.3 (4H, m),2.50 (3H, s), 3.2 (2H, brs), 3.5-3.6 (2H, m), 4.0-4.2 (2H, m), 4.9 (1H,q).

ESI/MS (m/z):225 (M+H)⁺.

INTERMEDIATE EXAMPLE 14

3-Amino-3-methylbutanoic acid

3-Methylcrotonic acid (12.0 g) was dissolved in pyridine (40 ml), andbenzyl amine (12.8 g) was added thereto, and the mixture was stirred for3 hours at 120° C. The reaction mixture was cooled to room temperature,and after acetone was added to the resulting suspension, crystals werecollected by filtration and washed. The crystals were dried underreduced pressure to give 3-benzylamino-3-methylbutanoic acid (10.3 g,Y.:42%) as colorless crystals.

ESI/MS:208 (M+H)⁺, 206 (M−H)⁻.

6 N Hydrochloric acid (5.8 ml) was added to a solution of the thusobtained 3-benzylamino-3-methylbutanoic acid (6.0 g) in ethanol (90 ml).5% Palladium on carbon (2.4 g) andacetic acid (46 ml) were added theretoand stirred for 5 hours at 50° C. in a hydrogen atmosphere. Insolublematter was removed by filtration, and the filtrate was concentratedunder reduced pressure. Precipitated crystals were washed with ether anddried under reduced pressure to give the title compound (4.4 g,Y.:quant.) as colorless crystals.

¹H NMR; (DMSO-d₆) δ (ppm):1.4 (6H, s), 2.7 (2H, s), 8.3 (3H, brs).

ESI/MS (m/z):118 (M+H)⁺, 116 (M−H)⁻.

INTERMEDIATE EXAMPLE 15

4-Methyl-1,4-pentanediamine

Methyl 4-methyl-4-nitropentanoate (5.00 g) was dissolved in ethanol (25ml), and 1 N sodium hydroxide solution was added thereto and stirred for1 day. The mixture was concentrated under reduced pressure, thenchloroform and water were added thereto, and the aqueous phase waswashed with chloroform. 2 N Hydrochloric acid (20 ml) was added to theaqueous phase which was then extracted with chloroform, and the extractwas dried over sodium sulfate anhydrous. The product was concentratedunder reduced pressure to give 4-methyl-4-nitropentanoic acid (4.32 g,Y.:94%) as white crystals.

¹H NMR; (CDCl₃) δ (ppm):1.6 (6H, s), 2.2-2.3 (2H, m), 2.4-2.5 (2H, m),10.8 (1H, brs).

The 4-methyl-4-nitropentanoic acid (4.3 g) obtained above was dissolvedin dichloromethane, and N-(3-dimethylaminopropyl)-N′-ethylcarbodiimidehydrochloride (6.1 g) and triethylamine (4.5 ml) were added thereto andstirred for 1 hour. Benzylamine (3.4 g) was added thereto and stirredfor 1 day. Water was added to the reaction mixture which was thenacidified by 2 N hydrochloric acid and extracted with chloroform. Theorganic phase was washed with a saturated sodium bicarbonate solutionand a saturated saline solution and dried over sodium sulfate anhydrous.The resulting product was concentrated under reduced pressure, and theresidue was purified by column chromatography (eluting solvent; ethylacetate:n-hexane 1:1.5) to give N-benzyl-4-methyl-4-nitropentanoic acidamide (2.5 g, Y.:38%) as a colorless oil.

¹H NMR; (CDCl₃) δ (ppm):1.6 (6H, s), 2.1-2.2 (2H, m), 2.2-3.3 (2H, m),4.4 (2H, d), 6.0 (1H, brs), 7.3-7.4 (5H, m).

The N-benzyl-4-methyl-4-nitropentanoic acid amide (2.5 g) obtained abovewas dissolved in tetrahydrofuran (20 ml) and cooled to 0° C. 1 N Boranetetrahydrofuran complex (13 ml) was added dropwise thereto and thenstirred overnight at room temperature. The reaction mixture was cooledagain to 0° C., and 2 N hydrochloric acid (30 ml) was added thereto,followed by heating to 50° C. The reaction solution was extracted withethyl acetate. The aqueous phase was alkalinized by 50% sodium hydroxidesolution, extracted with chloroform. The extract was washed with asaturated saline solution, and dried over sodium sulfate anhydrous. Theproduct was concentrated under reduced pressure to givebenzyl-4-methyl-4-nitropentylamine (1.7 g, Y.: 73%) as a colorless oil.

¹H NMR; (CDCl₃) δ (ppm):1.4-1.5 (2H, m), 1.6 (6H, s), 2.0 (2H, dt), 2.6(2H, t), 7.2-7.4 (5H, m).

The benzyl-4-methyl-4-nitropentylamine (1.7 g) obtained above and 10%palladium on carbon (500 mg) were suspended in ethanol and stirred for 1day at 60° C. in a hydrogen atmosphere. The reaction mixture was cooledto room temperature, filtered with celite and concentrated under reducedpressure. The resulting product was acidified by 2 N hydrochloric acidand extracted with ether. The aqueous phase was alkalinized by 50%sodium hydroxide solution, extracted with ether and dried over sodiumsulfate anhydrous. The product was concentrated under reduced pressureto give the title compound (420 mg, Y.:50%).

¹H NMR; (CDCl₃) δ (ppm):1.2 (6H, s), 1.5-1.6 (4H, m), 2.7-2.8 (2H, m).

INTERMEDIATE EXAMPLE 16

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid amide (475 mg) wasdissolved in ethanol (5 ml), and 5 N sodium hydroxide solution (2 ml)was added thereto and stirred for 1 hour at 70° C. The reaction mixturewas cooled to room temperature, water was added thereto, and thereaction mixture was washed with ethyl acetate. 2 N Hydrochloric acidwas added to the aqueous phase until it became acidic, and precipitatedcrystals were collected by filtration and washed with water andn-hexane. The crystals were dried under reduced pressure to give thetitle compound (300 mg, Y.:63%) as white crystals.

ESI/MS:178 (M+H)⁺, 176 (M−H⁻.

INTERMEDIATE EXAMPLE 17

2,5,7-Trimethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

3-Amino-5-methylpyrazole (970 mg) and ethyl diacetoacetate (1.7 g) weredissolved in acetic acid (5 ml) and stirred at 120° C. for 3 hours. Thereaction mixture was cooled to room temperature and concentrated underreduced pressure. Ethanol (5 ml) and 5 N sodium hydroxide solution (2ml) were added to the residue and stirred at 70° C. for 1 hour. Thereaction mixture was cooled to room temperature, and water was added tothe reaction mixture which was then washed with ethyl acetate. 2 NHydrochloric acid was added to the aqueous phase until it became acidic,and precipitated crystals were collected by filtration and washed withwater and n-hexane. The crystals were dried under reduced pressure togive the title compound (1.6 g, Y.:80%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.4 (3H, s), 2.5 (3H, s), 2.8 (3H, s), 6.5(1H, s), 13.8 (1H, brs).

ESI/MS (m/z):206 (M−H)⁻.

INTERMEDIATE EXAMPLE 18

7-Methoxy-2,5-dimethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

3-Amino-5-methylpyrazole (970 mg) and diethyl acetomalonate (2.0 g) weredissolved in acetic acid (5 ml) and stirred for 3 hours at 120° C. Thereaction mixture was cooled to room temperature and concentrated underreduced pressure, and ethanol was added to the residue which were thencooled to 0° C. Precipitated crystals were collected by filtration andwashed with cold ethanol. The crystals were dried under reduced pressureto give ethyl7-hydroxy-2,5-dimethylpyrazolo[1,5-a]pyrimidine-6-carboxylate (2.2 g,Y.:95%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):1.3 (3H, t), 2.3 (3H, s), 2.4 (3H, s), 4.2(2H, q), 6.0 (1H, s), 12.6 (1H, brs).

ESI/MS (m/z):236 (M+H)⁺, 234 (M−H)⁻.

The ethyl 7-hydroxy-2,5-dimethylpyrazolo[1,5-a]pyrimidine-6-carboxylate(235 mg) obtained above was suspended in acetone (5 ml), and potassiumcarbonate (138 mg) was added thereto and stirred for 30 minutes at roomtemperature. Methyl iodide (1.0 ml) was added to the mixture which wasthen refluxed for 2 hours. The reaction mixture was cooled to roomtemperature, then water was added to the reaction mixture which wasextracted with chloroform, and the organic phase was washed with asaturated saline solution and dried over sodium sulfate anhydrous. Theresulting product was concentrated under reduced pressure, and theresulting crystals were dissolved in ethanol (5 ml). 5 N Sodiumhydroxide solution (1 ml) was added thereto and stirred for 1 hour at50° C. The reaction mixture was cooled to room temperature, and waterwas added to the mixture which was then washed with ethyl acetate. 2 NHydrochloric acid was added to the aqueous phase until it became acidic,and precipitated crystals were collected by filtration and washed withwater and n-hexane. The crystals were dried under reduced pressure togive the title compound (162 mg, Y.:73%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.3 (3H, s), 2.7 (3H, s), 3.7 (3H, s), 6.4(1H, s).

ESI/MS (m/z):222 (M+H)⁺.

INTERMEDIATE EXAMPLE 19

5,7-Dimethyl-2-phenylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

3-Amino-5-phenylpyrazolo (1.6 g) and ethyl diacetoacetate (1.7 g) weredissolved in acetic acid (5.0 ml) and stirred for 3 hours at 120° C. Themixture was cooled to room temperature and concentrated under reducedpressure. Ethanol (10 ml) and 5 N sodium hydroxide solution (3 ml) wereadded to the residue and then stirred for 1 hour at 70° C. The mixturewas cooled to room temperature, and water was added to the mixture whichwas then washed with ethyl acetate. 2 N Hydrochloric acid was added tothe aqueous phase until it became acidic, and precipitated crystals werecollected by filtration and washed with water and n-hexane. The productwas dried under reduced pressure to give the title compound (2.1 g,Y.:78%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.6 (3H, s), 2.9 (3H, s), 7.2 (1H, s), 7.4(1H, t), 7.5 (2H, t), 8.1 (1H, d), 13.9 (1H, brs).

ESI/MS (m/z):266 (M−H)⁻.

INTERMEDIATE EXAMPLE 20

2-Methyl-7-trifluoromethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

3-Amino-5-methylpyrazole (389 mg) and ethyl(ethoxymethylidene)trifluoroacetoacetate (960 mg) were dissolved inethanol (10 ml) and stirred for 1.5 hours at 70° C. Conc. hydrochloricacid (1 mg) was added thereto, and the mixture was stirred foradditional 1 hour. The mixture was cooled to room temperature andconcentrated under reduced pressure. Ethanol (10 ml) and 5 N sodiumhydroxide solution (3 ml) were added to the residue and then stirred for1 hour at 70° C. The mixture was cooled to room temperature, and waterwas added to the mixture which was then washed with ethyl acetate. 2 NHydrochloric acid was added to the aqueous phase until it became acidic,and precipitated crystals were collected by filtration and washed withwater and n-hexane. The product was dried under reduced pressure to givethe title compound (102 mg, Y.:42%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.6 (3H, s), 2.9 (3H, s), 7.2 (1H, s), 7.4(1H, t), 7.5 (2H, t), 8.1 (1H, d), 13.9 (1H, brs).

ESI/MS (m/z):244 (M−H)⁻.

INTERMEDIATE EXAMPLE 21

2-t-Butyl-5,7-dimethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

3-Amino-5-t-butylpyrazole (1.6 g) and ethyl diacetoacetate (1.7 g) weredissolved in acetic acid (5 ml) and stirred for 3 hours at 120° C. Themixture was cooled to room temperature and concentrated under reducedpressure. Ethanol (10 ml) and 5 N sodium hydroxide solution (3 ml) wereadded to the residue and then stirred for 1 hour at 70° C. The mixturewas cooled to room temperature, and water was added to the mixture whichwas then washed with ethyl acetate. 2 N Hydrochloric acid was added tothe aqueous phase until it became acidic, and precipitated crystals werecollected by filtration and washed with water and n-hexane. The productwas dried under reduced pressure to give the title compound (2.1 g,Y.:78%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.6 (3H, s), 2.9 (3H, s), 7.2 (1H, s), 7.4(1H, t), 7.5 (2H, t), 8.1 (1H, d), 13.9 (1H, brs).

ESI/MS (m/z):246 (M−H)⁻.

INTERMEDIATE EXAMPLE 22

2-t-Butyl-7-methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

Ethyl acetoacetate (35.4 g) was dissolved in acetonitrile (200 ml), anddimethylformamide dimethyl acetal (30.9 g) was added thereto, and themixture was stirred overnight at room temperature. The reaction mixturewas concentrated under reduced pressure to give ethyl2-dimethylaminomethyleneacetoacetate (50.4 g, Y.:99%) as a red oil.

¹H NMR; (CDCl₃-d₆) δ (ppm):1.3 (3H, t), 2.3 (3H, s), 3.1 (6H, brs), 4.2(2H, q), 7.7 (1H, s).

The ethyl 2-dimethylaminomethyleneacetoacetate (556 mg) obtained aboveand 3-amino-5-t-butylpyrazole (418 mg) were dissolved in ethanol (10 ml)and stirred for 1.5 hours at 70° C. Conc. hydrochloric acid (1 ml) wasadded thereto, and the mixture was stirred for additional 1 hour. Themixture was cooled to room temperature and concentrated under reducedpressure. Ethanol (10 ml) and 5 N sodium hydroxide solution (3 ml) wereadded to the residue and then stirred for 1 hour at 70° C. The mixturewas cooled to room temperature, and water was added to the mixture whichwas then washed with ethyl acetate. 2 N Hydrochloric acid was added tothe aqueous phase until it became acidic, and precipitated crystals werecollected by filtration and washed with water and n-hexane. The productwas dried under reduced pressure to give the title compound (396 mg,Y.:57%) as yellow crystals.

1H NMR; (DMSO-d₆) δ (ppm):1.4 (9H, s), 3.1 (3H, s), 6.8 (1H, s), 8.8(1H, s), 13.5 (1H, brs).

ESI/MS (m/z):232 (M−H)⁻.

INTERMEDIATE EXAMPLE 23

7-Methyl-2-phenylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

3-Amino-5-phenylpyrazolo (477 mg) and ethyl2-N,N-dimethylaminomethyleneacetoacetate (556 mg) were dissolved inethanol (10 ml) and stirred for 1.5 hours at 70° C. Conc. Hydrochloricacid (1 ml) was added thereto, and the mixture was stirred foradditional 1 hour. The mixture was cooled to room temperature andconcentrated under reduced pressure. Ethanol (10 ml) and 5 N sodiumhydroxide solution (3 ml) were added to the residue and then stirred for1 hour at 70° C. The mixture was cooled to room temperature, and waterwas added to the mixture which was then washed with ethyl acetate. 2 NHydrochloric acid was added to the aqueous phase until it became acidic,and precipitated crystals were collected by filtration and washed withwater and n-hexane. The product was dried under reduced pressure to givethe title compound (463 mg, Y.:61%) as yellow crystals.

¹H NMR; (DMSO-d₆) δ (ppm):3.2 (3H, s), 7.4 (1H, s), 7.5 (3H, m), 8.1(2H, d), 8.9 (1H, s), 13.6 (1H, brs).

ESI/MS (m/z):252 (M−H)⁻.

INTERMEDIATE EXAMPLE 24

7-Methoxy-5-methyl-2-phenylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

3-Amino-5-phenylpyrazole (1.56 mg) and diethyl acetomalonate (2.00 g)were dissolved in acetic acid (5.0 ml) and stirred for 3 hours at 120°C. The reaction mixture was cooled to room temperature and concentratedunder reduced pressure. Ethanol was added to the residue which were thencooled to 0° C. Precipitated crystals were collected by filtration andwashed with cold ethanol. The crystals were dried under reduced pressureto give ethyl7-hydroxy-5-methyl-2-phenylpyrazolo[1,5-a]pyrimidine-6-carboxylate (2.73g, Y.:92%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):1.3 (3H, t), 2.4 (3H, s), 4.3 (2H, q), 6.7(1H, s), 7.4 (2H, t), 7.5 (2H, t), 8.0 (1H, d).

The ethyl7-hydroxy-5-methyl-2-phenylpyrazolo[1.5-a]pyrimidine-6-carboxylate (297mg) obtained above was suspended in acetone (5 ml), and potassiumcarbonate (138 mg) was added thereto and stirred for 30 minutes at roomtemperature. Methyl iodide (1.0 ml) was added to the mixture which wasthen refluxed for 2 hours. The reaction mixture was cooled to roomtemperature, and water was added to the reaction mixture which wasextracted with chloroform, and the organic phase was washed with asaturated saline solution and dried over sodium sulfate anhydrous. Theproduct was concentrated under reduced pressure, and the resultingcrystals were dissolved in ethanol (5 ml). 5 N Sodium hydroxide solution(1 ml) was added thereto and stirred for 1 hour at 50° C. The reactionmixture was cooled to room temperature, and water was added to themixture which was then washed with ethyl acetate. 2 N Hydrochloric acidwas added to the aqueous phase until it became acidic, and precipitatedcrystals were collected by filtration and washed with water andn-hexane. The crystals were dried under reduced pressure to give thetitle compound (121 mg, Y.:45%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.7 (3H, s), 3.8 (3H, s), 7.2 (1H, s), 7.5(1H, t), 7.5 (2H, dd), 8.0 (2H, d), 13.5 (1H, brs).

INTERMEDIATE EXAMPLE 25

5-Hydroxy-2-methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

Triethylamine (2.02 g) and benzyloxycarbonyl chloride (1.71 g) wereadded dropwise to a solution of 3-amino-5-methylpyrazole (971 mg) inchloroform (20 ml) at 0° C., and the mixture was stirred for 18 hours.The mixture was concentrated under reduced pressure, and the residue waspurified by column chromatography (eluting solvent; n-hexane:ethylacetate 2:1) to give benzyl 5-methyl-2H-pyrazol-3-ylcarbamate (1.65 g,Y.:67%).

A mixed solution of the benzyl 5-methyl-2H-pyrazol-3-ylcarbamate (600mg) obtained above and diethyl ethoxymethylenemalonate (1.80 g) wasstirred for 18 hours at 100° C. The reaction mixture was concentratedunder reduced pressure, and the residue was purified by columnchromatography (eluting solvent; n-hexane:ethyl acetate 3:1) to givediethyl2-(5-benzyloxycarbonylamino-3-methylpyrazol-1-ylmethylene)malonate (700mg, Y.: 67%).

4 N Hydrochloric acid/1,4-dioxane (2 ml) was added to the diethyl2-(5-benzyloxycarbonylamino-3-methylpyrazol-1-ylmethylene)m alonate (100mg) obtained above and stirred for 22 hours. Precipitated crystals werecollected by filtration and dried under reduced pressure to give ethyl5-hydroxy-2-methylpyrazolo[1,5-a]pyrimidine-6-carboxylate (40 mg,Y.:73%).

In a similar procedure as employed in the Intermediate Example 24, theethyl 5-hydroxy-2-methylpyrazolo[1,5-a]pyrimidine-6-carboxylate (154 mg)was hydrolyzed to give the title compound (136 mg, Y.: quant.).

¹H NMR; (DMSO-d₆) δ (ppm):2.3 (3H, s), 6.3 (1H, s), 8.6 (1H, s)

INTERMEDIATE EXAMPLE 26

7-Hydroxy-2-methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

In a similar procedure as employed in the Intermediate Example 24, ethyl7-methoxy-2-methylpyazolo[1,5-a]pyrimidine-6-carboxylate was hydrolyzedto give the title compound.

¹H NMR; (DMSO-d₆) δ (ppm):2.3 (3H, s), 6.3 (1H, s), 8.8 (1H, s).

INTERMEDIATE EXAMPLE 27

2-Hydroxymethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

Acetonitrile (2.04 ml) was added to a solution of sodium methoxide (1.40g) in tetrahydrofuran (50 ml) and refluxed for 1.5 hours. The mixturewas cooled to room temperature, and methyl methoxyacetate (2.57 ml) wasadded to the mixture which was then refluxed overnight. The reactionmixture was cooled to room temperature, water was added to the reactionmixture which was adjusted to pH 7 by 1 N hydrochloric acid andextracted with ether. The organic phase was washed with a saturatedsaline solution and dried over sodium sulfate anhydrous. The resultingproduct was concentrated under reduced pressure, and the residue waspurified by column chromatography (eluting solvent; n-hexane:ethylacetate 2:1) to give 4-methoxy-3-oxobutyronitrile (1.14 g, Y.:39%).

Hydrazine monohydrate (0.49 ml) was added to a solution of the thusobtained 4-methoxy-3-oxobutyronitrile (1.14 g) in ethanol (50 ml), andrefluxed for 17 hours. The reaction mixture was cooled to roomtemperature and concentrated under reduced pressure. The residue waspurified by column chromatography (eluting solvent;dichloromethane:methanol 50:1) to give5-methoxymethyl-2H-pyrazol-3-ylamine (684 mg, Y.:53%).

Ethyl 2-formyl-3-oxopropionate (775 mg) was added to a solution of thethus obtained 5-methoxymethyl-2H-pyrazol-3-ylamine (684 mg) in ethanol(50 ml), and stirred overnight. The reaction solution was concentratedunder reduced pressure, and a saturated sodium bicarbonate solution wasadded to the residue which were then extracted with ethyl acetate. Theorganic phase was washed with a saturated saline solution and dried oversodium sulfate anhydrous. The resulting product was concentrated underreduced pressure, and the residue was purified by column chromatography(eluting solvent; n-hexane:ethyl acetate 4:1) to give ethyl2-methoxymethylpyrazolo[1,5-a]pyrimidine-6-carboxylate (878 mg, Y.:69%).1 M Boron tribromide solution in dichloromethane (0.51 ml) was addeddropwise at −70° C. to a solution of the thus obtained ethyl2-methoxymethylpyrazolo[1,5-a]pyrimidine-6-carboxylate (20 mg) indichloromethane (2 ml). The temperature of the mixture under stirringwas increased from −70° C. to −50° C. over 4.5 hours and then increasedfrom −50° C. to room temperature over 2 hours. The reaction mixture wascooled to 0° C., water was added to the reaction mixture which was thenextracted with ethyl acetate, and the extract was dried over sodiumsulfate anhydrous. The resulting product was concentrated under reducedpressure to give ethyl2-hydroxymethylpyrazolo[1,5-a]pyrimidine-6-carboxylate (19 mg,Y.:quant.).

5 N Sodium hydroxide solution (0.1 ml) was added to a solution of thethus obtained ethyl2-hydroxymethylpyrazolo[1,5-a]pyrimidine-6-carboxylate (19 mg) intetrahydrofuran (1 ml), and stirred for 17 hours at room temperature.After water was added, the reaction mixture was washed with ethylacetate. The aqueous phase was acidified by 2 N hydrochloric acid,extracted with ethyl acetate and dried over sodium sulfate anhydrous.The resulting product was concentrated under reduced pressure, and theresidue was dissolved in hot ethyl acetate and then filtered. Thefiltrate was concentrated under reduced pressure to give the titlecompound (11 mg, Y.:65%).

¹H NMR; (DMSO-d₆) δ (ppm):4.7 (2H, s), 6.8 (1H, s), 8.8 (1H, d), 9.3-9.4(1H, m).

INTERMEDIATE EXAMPLE 28

2-Methoxymethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid

In a similar procedure as employed in the Intermediate Example 27, ethyl2-methoxymethylpyrazolo[1,5-a]pyrimidine-6-carboxylate as theintermediate in Intermediate Example 27 was hydrolyzed to give the titlecompound.

¹H NMR; (DMSO-d₆) δ (ppm):3.4 (3H, s), 4.6 (2H, s), 6.8 (1H, s), 8.9(1H, d), 9.4-9.5 (1H, m).

ESI/MS (m/z):206 (M−H)⁻.

INTERMEDIATE EXAMPLE 29

1-Methyl-1H-indole-3-carboxylic acid

1H-Indole-3-carboxylic acid (960 mg) was dissolved inN,N-dimethylformamide (15 ml) and cooled to 0° C. Sodiumhydride (720 mg)was added in two divided portions thereto, and the mixture was warmed toroom temperature and stirred for 1 hour. The mixture was cooled again to0° C., and a solution of methyl iodide (0.67 ml) inN,N-dimethylformamide (5 ml) was added slowly dropwise thereto, and themixture was warmed to room temperature and stirred for 2 hours. Thereaction mixture was cooled to 0° C., then ice was added thereto, water(50 ml) was further added thereto, and precipitated crystals werecollected by filtration and washed with water and n-hexane. The productwas dried under reduced pressure to give the title compound (910 mg,Y.:87%) as yellow crystals.

¹H NMR; (DMSO-d₆) δ (ppm):3.9 (3H, s), 7.2 (1H, dd), 7.3 (1H, dd), 7.5(1H, d), 8.0 (1H, d), 8.1 (1H, s), 11.9 (1H, brs).

ESI/MS (m/z):174 (M−H)⁻.

In a similar procedure as employed in the Intermediate Example 29,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in Table 2.

TABLE 2 Intermediate Example Compound Name ESI/MS(m/z) 301-methyl-1H-indole-4-carboxylic 174 (M − H)⁻ acid 311-methyl-1H-indole-5-carboxylic 176 (M + H)⁺ acid 174 (M − H)⁻ 321-methyl-1H-indole-6-carboxylic 176 (M + H)⁺ acid 174 (M − H)⁻

INTERMEDIATE EXAMPLE 33

1-Methyl-1H-indole-7-carboxylic acid

Methyl 1H-indole-7-carboxylate (546 mg) was dissolved inN,N-dimethylformamide (8 ml) and cooled to 0° C. Sodium hydride (370 mg)was added thereto and stirred as such for 30 minutes. Methyl iodide(0.38 ml) was added slowly dropwise thereto, and the mixture was warmedto room temperature and stirred for 2 hours. The mixture was dilutedwith ethyl acetate, and the organic phase was washed with 2 Nhydrochloric acid, a saturated sodium bicarbonate solution and asaturated saline solution.

The resulting product was dried over sodium sulfate anhydrous and thenconcentrated under reduced pressure.

1,4-Dioxane (14 ml) and 1 N sodium hydroxide solution (14 ml) were addedto the above compound and stirred for 17 hours at 40° C. The mixture wasacidified by 2 N hydrochloric acid and extracted with chloroform. Theextract was dried over sodium hydrous and then concentrated underreduced pressure. Precipitates were collected by filtration, washed withn-hexane and dried under reduced pressure to give the title compound(296 mg, Y.:55%).

¹H NMR (DMSO-d₆) δ (ppm):3.8 (1H, s), 6.5 (1H, d), 7.1 (1H, t), 7.4 (1H,d), 7.5 (1H, dd), 7.7 (1H, dd).

ESI/MS (m/z):176 (M+H)⁺, 174 (M−H)⁻.

In a similar procedure as employed in the Intermediate Example 33,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in Table 3.

TABLE 3 Intermediate Example Compound Name ESI/MS(m/z) 344-methoxy-1-methyl-1H-indole-2- 204 (M − H)⁻ carboxylic acid 356-methoxy-1-methyl-1H-indole-2- 206 (M + H)⁺ carboxylic acid 204 (M −H)⁻ 36 4,6-dimethoxy-1-methyl-1H-indole- 236 (M + H)⁺ 2-carboxylic acid234 (M − H)⁻ 37 5-methoxy-1,2-dimethyl-1H-indole- 220 (M + H)⁺3-carboxylic acid 218 (M − H)⁻

INTERMEDIATE EXAMPLE 38

5-Methoxy-1-methyl-1H-indole-3-carboxylic acid

4-Methoxyphenylhydrazine hydrochloride (200 mg) and methyl3,3-dimethoxypropionate (194 mg) were added to acetic acid (8.0 ml) andstirred for 4.5 hours at 70° C. The mixture was concentrated underreduced pressure, and the residue was purified by column chromatography(eluting solvent; ethyl acetate:n-hexane 1:5→1:3) to give methyl5-methoxy-1H-indole-3-carboxylate (259 mg, Y.:97%).

¹H NMR; (DMSO-d₆) δ (ppm):3.8 (3H, s), 3.9 (3H, s), 6.8 (1H, dd), 7.4(1H, d), 7.5 (1H, d), 8.0 (1H, s), 11.8 (1H, brs).

ESI/MS (m/z):204 (M−H)⁻.

The methyl 5-methoxy-1H-indole-3-carboxylate (121 mg) obtained above wasdissolved in N,N-dimethylformamide (1.5 ml) and cooled to 0° C. Sodiumhydride (47 mg) was added thereto and stirred as such for 30 minutes.Methyl iodide (55 μl) was added dropwise thereto, and the mixture waswarmed to room temperature and stirred for 1 hour. The reaction mixturewas diluted with ethyl acetate, and the organic phase was washed with 2N hydrochloric acid, a saturated sodium bicarbonate solution and asaturated saline solution. The resulting product was dried over sodiumsulfate anhydrous and concentrated under reduced pressure.

1,4-Dioxane (4 ml) and 1 N sodium hydroxide solution (4 ml) were addedto the above compound and stirred for 18 hours at 40° C. The mixture wasacidified by 2 N hydrochloric acid, and precipitates were collected byfiltration, washed with water and dried under reduced pressures to givethe title compound (57 mg, Y.:52%).

¹H NMR; (DMSO-d₆) δ (ppm):3.7 (3H, s), 3.8 (3H, s), 6.8 (1H, dd), 7.4(1H, d), 7.5 (1H, d), 7.9 (1H, s), 11.9 (1H, brs).

ESI/MS (m/z):206 (M+H)⁺, 204 (M−H)⁻.

INTERMEDIATE EXAMPLE 39

7-Methoxy-1-methyl-1H-indole-5-carboxylic acid

According to a method described in a literature (J. Org. Chem., 1996,61, 5804-5812), the title compound was obtained from methyl3-methoxy-4-anthranylate.

¹H NMR; (DMSO-d₆) δ (ppm):3.9 (3H, s), 4.0 (3H, s), 6.5 (1H, d), 7.2(1H, s), 7.3 (1H, d), 7.9 (1H, s).

ESI/MS (m/z):206 (M+H)⁺, 204 (M−H)⁻.

INTERMEDIATE EXAMPLE 40

1-(2,2-Dimethylpropyl)-1H-indole-3-carboxylic acid

1H-Indole-3-carboxylic acid (208 mg) was dissolved inN,N-dimethylformamide (10 ml), then sodium hydride (154 mg) was addedthereto, and the mixture was stirred for 10 minutes at room temperature.Neopentyl iodide (0.25 ml) was added to the reaction solution andstirred for 15 hours at 80° C. Water was added to the reaction mixturewhich was then washed with ethyl acetate. The aqueous phase was adjustedto pH 6 by 1 N hydrochloric acid, extracted with ethylacetate, and theextract was washed with a saturated saline solution and dried oversodium sulfate anhydrous. The resulting product was concentrated underreduced pressure, and the residue was purified by column chromatography(eluting solvent; n-hexane:ethyl acetate 4:1) to give the title compound(264 mg, Y.:89%).

¹H NMR; (CDCl₃) δ (ppm):1.0 (9H, s), 3.9 (2H, s), 7.2-7.3 (2H, m),7.3-7.4 (1H, m), 7.9 (1H, s), 8.2-8.3 (1H, m).

ESI/MS (m/z):232 (M+H)⁺, 230 (M−H)⁻.

INTERMEDIATE EXAMPLE 41

1-Isobutyl-1H-indole-3-carboxylic acid

In a similar procedure as employed in the Intermediate Example 40, thetitle compound (121 mg, Y.:36%) was obtained by using1H-indole-3-carboxylic acid (251 mg) and isobutyl iodide.

1H NMR; (CDCl₃) δ (ppm):0.9 (6H, d), 2.2-2.3 (1H, m), 3.9 (2H, d),7.2-7.3 (2H, m), 7.3-7.4 (1H, m), 7.9 (1H, s), 8.2-8.3 (1H, m).

ESI/MS (m/z):218 (M+H)⁺, 216 (M−H)⁻.

INTERMEDIATE EXAMPLE 42

1-(2,2-Dimethylpropyl)-1H-indole-5-carboxylic acid

In a similar procedure as employed in the Intermediate Example 40, thetitle compound (473 mg, Y.:43%) was obtained by using methyl1H-indole-5-carboxylate (825 mg) and neopentyl iodide.

¹H NMR; (CDCl₃) δ (ppm):1.0 (9H, s), 3.9 (2H, s), 6.6 (1H, d), 7.1 (1H,d), 7.3 (1H, d), 7.9 (1H, dd), 8.4 (1H, s).

ESI/MS (m/z):232 (M+H)⁺, 230 (M−H)⁻.

INTERMEDIATE EXAMPLE 43

1-Isobutyl-1H-indole-5-carboxylic acid

In a similar procedure as employed in the Intermediate Example 40, thetitle compound (375 mg, Y.:30%) was obtained by using methyl1H-indole-5-carboxylate (1.02 g) and isobutyl iodide.

¹H NMR; (CDCl₃) δ (ppm):0.9 (6H, d), 2.1-2.2 (1H, m), 3.9 (2H, d), 6.6(1H, d), 7.1 (1H, d), 7.3 (1H, d), 7.9 (1H, dd), 8.4 (1H, s).

ESI/MS (m/z):218 (M+H)⁺, 216 (M−H)⁻.

INTERMEDIATE EXAMPLE 44

1-Benzyloxymethyl-1H-indole-3-carboxylic acid

Methyl 1H-indole-3-carboxylate (1.00 g) was dissolved inN,N-dimethylformamide (12 ml) and cooled to 0° C. Sodium hydride (0.46g) was added to the solution in two divided portions, and stirred assuch for 30 minutes. Benzyloxymethyl chloride (2.4 ml) was added slowlydropwise thereto, and the mixture was warmed to room temperature andstirred for 2 hours. The reaction mixture was diluted with ethylacetate, and the organic phase was washed with 2 N hydrochloric acid, asaturated sodium bicarbonate solution and a saturated saline solution.The resulting product was dried over sodium sulfate anhydrous andconcentrated under reduced pressure.

1,4-Dioxane (20 ml) and 1 N sodium hydroxide solution (20 ml) were addedto the above compound, and the mixture was stirred for 18 hours at 40°C. The reaction mixture was acidified by 2N hydrochloric acid andextracted with chloroform. The extract was dried over sodium sulfateanhydrous and concentrated under reduced pressure. The residue wascrystallized from n-hexane and dried under reduced pressure to give thetitle compound (1.3 g, Y. :83%).

¹H NMR; (DMSO-d₆) δ (ppm):5.7 (2H, s), 7.2-7.4 (7H, m), 7.6 (1H, d), 8.0(1H, d), 8.2 (1H, s).

ESI/MS (m/z):282 (M+H)⁺, 280 (M−H)⁻.

INTERMEDIATE EXAMPLE 45

1-Methoxymethyl-1H-indole-3-carboxylic acid

Methyl 1H-indole-3-carboxylate (500 mg) was dissolved inN,N-dimethylformamide (7.5 ml) and cooled to 0° C. Sodium hydride (340mg) was added thereto and stirred as such for 30 minutes. Methoxymethylchloride (0.43 ml) was added slowly dropwise thereto, and the mixturewas warmed to room temperature and stirred for 1 hour. The reactionmixture was diluted with ethyl acetate, and the organic phase was washedwith 2 N hydrochloric acid, a saturated sodium bicarbonate solution anda saturated saline solution. The resulting product was dried over sodiumsulfate anhydrous and then concentrated under reduced pressure.

1,4-Dioxane (15 ml) and 1 N sodium hydroxide solution (15 ml) were addedto the above compound and stirred for 16 hours at 40° C. The reactionmixture was acidified by 2 N hydrochloric acid and extracted withchloroform. The extract was dried over sodium sulfate anhydrous and thenconcentrated under reduced pressure. Precipitates were collected byfiltration, washed with ether and dried under reduced pressure to givethe title compound (342 mg, Y.:58%).

¹H NMR; (DMSO-d₆) δ (ppm):3.1 (3H, s), 5.6 (2H, s), 7.2-7.3 (2H, m), 7.6(1H, d), 8.0 (1H, d), 8.2 (1H, d).

ESI/MS (m/z):206 (M+H)⁺, 204 (M−H)⁻.

INTERMEDIATE EXAMPLE 46

1-Acetoxymethyl-1H-indole-3-carboxylic acid

1H-Indole-3-carboxylic acid (400 mg) was dissolved inN,N-dimethylformamide (6 ml) and cooled to 0° C. Sodium hydride (500 mg)was added to the solution in two divided portions, and the mixture wasstirred as such for 30 minutes. Bromomethyl acetate (0.32 ml) was addedslowly dropwise thereto, and the mixture was stirred for 15 minutes at0° C., warmed to room temperature and stirred for 45 minutes. Themixture was cooled to 0° C., and water was added to the mixture whichwas then acidified by 2 N hydrochloric acid and extracted with ethylacetate. The extract was dried over sodium sulfate anhydrous andconcentrated under reduced pressure. The residue was purified by columnchromatography (eluting solvent; dichloromethane:methanol 50:1) to givethe title compound (354 mg, Y.:61%).

¹H NMR; (DMSO-d₆) δ (ppm):2.0 (3H, s), 6.2 (2H, s), 7.2-7.4 (2H, m), 7.6(1H, d), 7.9 (1H, s), 8.0 (1H, d).

ESI/MS (m/z):233 (M+H)⁺.

INTERMEDIATE EXAMPLE 47

1-Benzyloxymethyl-1H-indole-5-carboxylic acid

Methyl 1H-indole-5-carboxylate (500 mg) was dissolved inN,N-dimethylformamide (6.0 ml). The solution was cooled to 0° C., andsodium hydride (230 mg) was added thereto and stirred for 30minutes.Benzylchloromethylether (1.2ml) was added thereto, and the mixture wasstirred for 2 hours at room temperature. The reaction solution wasextracted with ethyl acetate, and the organic phase was washed with 2 Nhydrochloric acid, a saturated sodium bicarbonate solution and asaturated saline solution. The resulting product was dried over sodiumsulfate anhydrous and then concentrated under reduced pressure.1,4-Dioxane (10 ml) and 1 N sodium hydroxide solution (5 ml) were addedto the residue and stirred for 22 hours at 40° C. The reaction mixturewas acidified by 2 N hydrochloric acid and then extracted withchloroform. The extract was dried over sodium sulfate anhydrous and thenconcentrated under reduced pressure. Precipitates were collected byfiltration, washed with n-hexane and dried under reduced pressure togive the title compound (740 mg, Y.: 92%).

¹H NMR; (DMSO-d₆) δ (ppm):4.4 (2H, s), 5.7 (2H, s), 6.6 (1H, d), 7.2-7.4(5H, m), 7.6-7.7 (3H, m), 7.8 (1H, d), 8.2 (1H, s)

ESI/MS (m/z):280 (M−H)⁻.

INTERMEDIATE EXAMPLE 48

1-Hydroxymethyl-1H-indole-5-carboxylic acid

The 1-benzyloxymethyl-1H-indole-5-carboxylic acid (380 mg) obtained inIntermediate Example 47 was suspended in ethanol (6.5 ml). 10% Palladiumon carbon (190 mg) was added thereto and stirred for 47 hours at 60° C.in a hydrogen atmosphere. Insoluble matter was removed by filtration,and the filtrate was concentrated under reduced pressure. The residuewas purified by column chromatography (eluting solvent;dichloromethane:methanol 50:1) to give the title compound (120 mg,Y.:48%).

¹H NMR; (DMSO-d₆) δ (ppm):5.5 (2H, s), 6.5 (1H, d), 7.5 (1H, d), 7.6(1H, d), 7.7 (1H, d), 8.2 (1H, s).

INTERMEDIATE EXAMPLE 49

1-Methoxymethyl-1H-indole-5-carboxylic acid

In a similar procedure as employed in the Intermediate Example 45, thetitle compound (190 mg, Y.:70%) was obtained from methyl1H-indole-5-carboxylate (500 mg) and chloromethyl methyl ether (0.43ml).

¹H NMR; (DMSO-d₆) δ (ppm):5.5 (2H, s), 6.5 (1H, d), 7.5 (1H, d), 7.6(1H, d), 7.7 (1H, d), 8.2 (1H, s).

INTERMEDIATE EXAMPLE 50

1-(2,2-Dimethylpropyl )-5-methoxy-1H-indole-3-carboxylic acid

Methyl 5-methoxy-1H-indole-5-carboxylate (357 mg) was dissolved inN,N-dimethylformamide (17 ml). Sodium hydride (209 mg) was added theretoin three divided portions and stirred as such for 15 minutes. Neopentyliodide (0.35 ml) was added dropwise thereto and stirred for 15 hours at80° C. The reaction mixture was diluted with ethyl acetate, and theorganic phase was washed with 2 N hydrochloric acid, a saturated sodiumbicarbonate solution and a saturated saline solution. The resultingproduct was dried over sodium sulfate anhydrous and then concentratedunder reduced pressure. The residue was purified by preparativethin-layer chromatography (developing solvent; ethyl acetate:n-hexane1:3) to give neopentyl1-(2,2-dimethylpropyl)-5-methoxy-1H-indo-3-carboxylate (114 mg, Y.:20%)and methyl 1-(2,2-dimethylpropyl)-5-methoxy-1H-indole-3-carboxylate (130mg, Y.: 27%).

1,4-Dioxane (2.5 ml) and 1 N sodium hydroxide solution (2.5 ml) wereadded to the neopentyl1-2,2-dimethylpropyl)-5-methoxy-1H-indole-3-carboxylate (114 mg)obtained above, and the mixture was stirred for 15 hours at 40° C.Ethanol (3 ml) was added thereto and the mixture was stirred for 24hours at 70° C. The reaction mixture was acidified by 2 N hydrochloricacid and extracted with chloroform. The extract was dried over sodiumsulfate anhydrous and then concentrated under reduced pressure to givethe title compound (73 mg, Y.:81%).

¹H NMR; (DMSO-d₆) δ (ppm):0.9 (9H, s), 3.7 (3H, s), 4.0 (2H, s), 6.8(1H, dd), 7.4 (1H, d), 7.5 (1H, d), 7.8 (1H, s).

ESI/MS (m/z):262 (M+H)⁺, 260 (M−H)⁻.

INTERMEDIATE EXAMPLE 51

1-2,2-Dimethylpropyl)-5-methyl-1H-indole-3-carboxylic acid

From methyl 5-methyl-1H-indole-3-carboxylate, the title compound wasobtained in the similar procedure as in Intermediate Example 50.

¹H NMR; (DMSO-d₆) δ (ppm):0.9 (9H, s), 2.4 (3H, s), 4.0 (2H, s), 7.0(1H, d), 7.4 (1H, d), 7.8 (1H, s), 7.8 (1H, s).

ESI/MS (m/z):246 (M+H)⁺, 244 (M−H)⁻.

INTERMEDIATE EXAMPLE 52

1-2,2-Dimethylpropyl)-5-methyl-1H-indole-3-carboxylic acid

1-2,2-Dimethylpropyl)-5-methoxy-1H-indole-3-carboxylic acid (102 mg) wasdissolved in dichloromethane (3 ml) and cooled to −78° C. 1 M Borontribromide solution in dichloromethane (1.2 ml) was added slowlydropwise thereto, and the mixture was stirred for 1 hour while thetemperature was returned from −78° C. to 0° C. The reaction mixture wasdiluted with chloroform and alkalinized by 1 N sodium hydroxidesolution, and the organic phase was separated. The aqueous phase wasacidified by 2 N hydrochloric acid, extracted with chloroform and driedover sodium sulfate anhydrous. The product was concentrated underreduced pressure to give the title compound (78 mg, Y.:80%).

1H NMR; (DMSO-d₆) δ (ppm):0.9 (9H, s), 3.9 (2H, s), 6.6 (1H, dd),7.3-7.4 (2H, m), 7.8 (1H, s), 8.9 (1H, brs).

ESI/MS (m/z):248 (M+H)⁺, 246 (M−H)⁻.

INTERMEDIATE EXAMPLE 53

1-(2,2-Dimethylpropionyloxymethyl)-1H-indole-3-carboxylic acid

Sodium hydride (218 mg) was added to a solution of1H-indole-3-carboxylic acid (400 mg) in N,N-dimethylformamide (4 ml)with ice cooling, and the mixture was stirred for 30 minutes.Chloromethyl2,2-dimethylpropionate (373 mg) was added thereto, and themixture was warmed to room temperature and stirred for 2 hours. Waterwas added thereto, and the aqueous phase was washed with ether. Theaqueous phase was acidified by 2 N hydrochloric acid and extracted withether. The organic phase was washed with a saturated saline solution anddried over sodium sulfate anhydrous. The product was concentrated underreduced pressure to give the title compound (540 mg, Y.:79%) as orangecrystals.

ESI/MS (m/z):276 (M+H)⁺, 274 (M−H)⁻.

INTERMEDIATE EXAMPLE 54

1-t-Butoxycarbonylmethyl-1H-indole-5-carboxylic acid

Sodium hydride (115 mg) was added to a solution of benzyl1H-indole-5-carboxylate (600 mg) in N,N-dimethylformamide (2 ml) withice cooling, and the mixture was stirred for 30 minutes. t-Butylbromoacetate (562 mg) was added thereto and stirred for 2 hours. Waterwas added thereto, and the aqueous phase was neutralized and thenextracted with dichloromethane. The organic phase was dried over sodiumsulfate anhydrous. The product was concentrated under reduced pressureto give benzyl 1-t-butoxycarbonylmethyl-1H-indole-5-carboxylate (944 mg,Y.: quant.).

The benzyl 1-t-butoxycarbonylmethyl-1H-indole-5-carboxylate (800 mg)obtained above was dissolved in ethanol, then 5% palladium on carbon(160 mg) was added thereto, and the mixture was stirred overnight atroom temperature in a hydrogen atmosphere. Insoluble matter was removedby filtration, and the filtrate was concentrated under reduced pressureto give the title compound (670 mg, Y.:quant.).

ESI/MS (m/z):276 (M+H)⁺, 274 (M−H)⁻.

INTERMEDIATE EXAMPLE 55

1-Methyl-2,3-dihydro-1H-indole-5-carboxylic acid

Dichloromethane (2 ml) and triethylsilane (1 ml) were added to1-methyl-1H-indole-5-carboxylic acid (100 mg). The mixture was cooled to0° C., trifluoroacetic acid (1 ml) was added dropwise thereto, and themixture was warmed to room temperature and stirred for 2 hours. Thereaction mixture was concentrated under reduced pressure, andprecipitate was collected by filtration. The precipitate was washed withether and dried under reduced pressure to give the title compound (66mg, Y.:65%).

¹H NMR; (DMSO-d₆) δ (ppm):2.7 (3H, s), 2.9 (2H, t), 3.4 (2H, t), 6.4(1H, d), 7.5 (1H, s), 7.6 (1H, d).

ESI/MS (m/z):178 (M+H)⁺, 176 (M−H)⁻.

INTERMEDIATE EXAMPLE 56

1-Acetyl-1H-indole-3-carboxylic acid

1H-Indole-3-carboxylic acid (400 mg) and sodium acetate (0.96 g) weresuspended in acetic anhydride (4.8 ml). The mixture was stirred at 110°C. for 16 hours and extracted with chloroform. The organic phase waswashed with 2 N hydrochloric acid, dried over sodium sulfate anhydrous,and concentrated under reduced pressure. The residue was purified bycolumn chromatography (eluting solvent; dichloromethane:methanol 50:1)to give the title compound (170 mg, Y.:34%).

¹H NMR; (DMSO-d₆) δ (ppm):2.7 (3H, s), 7.3-7.4 (2H, m), 8.0-8.1 (1H, m),8.3-8.4 (1H, m), 8.4-8.5 (1H, m).

ESI/MS (m/z):202 (M−H)⁻.

INTERMEDIATE EXAMPLE 57

1-Acetyl-2,3-dihydro-1H-indole-5-carboxylic acid

1H-Indole-5-carboxylic acid (2.0 g) was dissolved inN,N-dimethylformamide (15 ml). Benzyl chloride (1.53 ml) and calciumcarbonate (3.4 g) were added to the solution and stirred for 39 hours atroom temperature. The mixture was diluted with ethyl acetate, and theorganic phase was washed with 2 N hydrochloric acid, a saturated sodiumbicarbonate solution and a saturated saline solution. The resultingproduct was dried over sodium sulfate anhydrous and then concentratedunder reduced pressure. Precipitated solids were collected byfiltration, washed with n-hexane and dried under reduced pressure togive 1H-benzyl indole-5-carboxylate (2.6 g, Y.:85%).

¹H NMR; (DMSO-d₆) δ (ppm):5.3 (2H, s), 6.6 (1H, s), 7.3-7.5 (7H, m), 7.7(1H, d), 8.3 (1H, s), 11.5 (1H, brs).

ESI/MS (m/z):252 (M+H)⁺, 250 (M−H)⁻.

The 1H-benzyl indole-5-carboxylate (1.0g) obtained above was dissolvedin N,N-dimethylformamide (10 ml). After the solution was cooled to 0°C., sodium hydride (0.32 g) was added to the solution which was thenstirred for 30 minutes. Acetyl chloride (1.3 ml) was added thereto, andthe mixture was stirred for 8 hours at room temperature. The reactionmixture was diluted with ethyl acetate, and the organic phase was washedwith 2 N hydrochloric acid, a saturated sodium bicarbonate solution anda saturated saline solution. The organic phase was dried over sodiumsulfate anhydrous and concentrated under reduced pressure. The residuewas purified by colunm chromatography (eluting solvent; ethylacetate:n-hexane 1:7→1:4) to give benzyl1-acetyl-1H-indole-5-carboxylate (1.1 g, Y. 97%).

¹H NMR; (DMSO-d₆) δ (ppm):2.6 (3H, s), 5.3 (2H, s), 6.9 (1H, d), 7.3-7.5(5H, m), 7.9 (1H, dd), 7.9 (1H, d), 8.3 (1H, d), 8.4 (1H, d).

ESI/MS (m/z):294 (M+H)⁺, 292 (M−H)⁻.

The benzyl 1-acetyl-1H-indole-5-carboxylate (550 mg) obtained above wassuspended in ethanol (9 ml). 10% Palladium on carbon was added thereto,and the mixture was stirred for 16 hours at room temperature in ahydrogen atmosphere. Insoluble matter was removed by filtration, and thefiltrate was concentrated under reduced pressure. Precipitated crystalswere collected by filtration, washed with ether and dried under reducedpressure to give the title compound (180 mg, Y.:48%).

¹H NMR; (DMSO-d₆) δ (ppm):2.1 (3H, s), 3.1 (2H, t), 4.1 (2H, t), 7.7-7.8(2H, m), 8.0 (1H, d).

ESI/MS (m/z):206 (M+H)⁺, 204 (M−H)⁻.

INTERMEDIATE EXAMPLE 58

1-Acetyl-1H-indole-5-carboxylic acid

1-Acetyl-2,3-dihydro-1H-indole-5-carboxylic acid (100 mg) was suspendedin 1,4-dioxane (3 ml), and 2,3-dichloro-5,6-dicyano-p-benzoquinone (445mg) was added thereto and stirred for 16 hours at 110° C. Solids wereremoved by filtration, and the filtrate was concentrated under reducedpressure. The residue was purified by preparative thin-layerchromatography (developing solvent; dichloromethane:methanol 20:1) togive the title compound (98 mg, Y.:99%).

¹H NMR; (DMSO-d₆) δ (ppm):2.6 (3H, s), 6.8 (1H, d), 7.9 (1H, d), 7.9(1H, d), 8.2 (1H, s), 8.3 (1H, d)

ESI/MS (m/z):203 (M+H)⁺, 202 (M−H)⁻.

INTERMEDIATE EXAMPLE 59

1-Benzoyl-1H-indole-5-carboxylic acid

Sodium hydride (58 mg) was added to a solution of benzyl1H-indole-5-carboxylate (300 mg) in N,N-dimethylformamide (2 ml) withice cooling, and then stirred for 30 minutes. Benzoyl chloride (202 mg)was added thereto, and the mixture was stirred for 2 hours. The reactionmixture was diluted with dichloromethane, and the organic phase waswashed with 2 N hydrochloric acid, a saturated sodium bicarbonatesolution and a saturated saline solution. The organic phase was driedover sodium sulfate anhydrous. The product was concentrated underreduced pressure to give benzyl 1-benzoyl-1H-indole-5-carboxylate (500mg, Y.:quant.) as pale orange crystals.

The benzyl 1-benzoyl-1H-indole-5-carboxylate (100 mg) obtained above wasdissolved in ethanol, and 5% palladium on carbon (20 mg) was addedthereto and stirred overnight at room temperature in a hydrogenatmosphere. Insoluble matter was removed by filtration, and the filtratewas concentrated under reduced pressure to give the title compound (50mg, Y.:66%) as white crystals.

ESI/MS (m/z):266 (M+H)⁺, 264 (M−H)⁻.

INTERMEDIATE EXAMPLE 60

1-(2,2-Dimethylpropionyl)-1H-indole-5-carboxylic acid

Sodium hydride (53 mg) was added to a solution of benzyl1H-indole-5-carboxylate (276 mg) in N,N-dimethylformamide (2 ml) withice cooling, and the mixture was stirred for 30 minutes.2,2-Dimethylpropionyl chloride (162 mg) was added thereto, and themixture was stirred for 2 hours. Water was added thereto, and theaqueous phase was neutralized, extracted with dichloromethane, and theextract was dried over sodium sulfate anhydrous. The resulting productwas concentrated under reduced pressure to give benzyl1-(2,2-dimethylpropionyl)-1H-indole-5-carboxylate (320 mg, Y.:87%) aspale orange crystals.

The benzyl 1-(2,2-dimethylpropionyl)-1H-indole-5-carboxylate (220 mg)obtained above was dissolved in ethanol, and 5% palladium on carbon (44mg) was added thereto and stirred overnight at room temperature in ahydrogen atmosphere. Insoluble matter was removed by filtration, and thefiltrate was concentrated under reduced pressure to give the titlecompound (140 mg, Y.:86%).

ESI/MS (m/z):246 (M+H)⁺, 244 (M−H)⁻.

INTERMEDIATE EXAMPLE 61

4-Methoxybenzothiazole-6-carboxylic acid

4-Amino-3-methoxybenzoic acid (1.0 g) and ammonium thiocyanate (910 mg)were dissolved in methanol (15 ml). A solution of bromine (0.30 ml) inmethanol (3.0 ml) was added slowly dropwise thereto at 0° C. Thereafter,the mixture was stirred for 2 hours at room temperature, and ice (50 g)was added thereto. Precipitated crystals were collected by filtrationand dried under reduced pressure to give white crystals (760 mg) whichwere then stirred for 2 hours at 90° C. together with sodium sulfide(1.6 g) in a mixed solvent of water (3.0 ml) and ethanol (3.0 ml). Aftercooling, the reaction mixture was acidified by 90% formic acid, thenprecipitated crystals were collected by filtration and dried underreduced pressure to give 4-amino-5-mercapto-3-methoxybenzoic acid (670mg, Y.:57%) as yellow crystals.

¹H NMR; (DMSO-d₆) δ (ppm):3.8 (3H, s), 7.1 (1H, brs), 7.4 (1H, brs).

ESI/MS (m/z):200 (M+H)⁺, 198 (M−H)⁻.

The 4-amino-5-mercapto-3-methoxybenzoic acid (670 mg) obtained above washeated at 50° C. in 90% formic acid (6.0 ml), and zinc powder (15 mg)was added thereto. The mixture was stirred for 2 hours at 100° C. andthen cooled to room temperature, and precipitated crystals werecollected by filtration, washed with water and dried under reducedpressure to give the title compound (470 mg, Y.:67%) as white crystals.

1H NMR; (DMSO-d₆) δ (ppm):4.0 (3H, s), 7.5 (1H, d), 8.3 (1H, d), 9.4(1H, s).

ESI/MS (m/z):210 (M+H)⁺, 208 (M−H)⁻.

INTERMEDIATE EXAMPLE 62

5-Methoxybenzothiazole-6-carboxylic acid

By the similar procedure as in Intermediate Example 61, the titlecompound (1.3 g, Y.:38%) was obtained from 4-amino-2-methoxybenzoic acid(2.8 g).

ESI/MS (m/z):210 (M+H)⁺, 208 (M−H)⁻.

INTERMEDIATE EXAMPLE 63

4-Methoxy-2-methylbenzothiazole-6-carboxylic acid

4-Amino-3-mercapto-5-methoxybenzoic acid (500 mg) was dissolved intetrahydrofuran (15 ml) and cooled at −78° C. Acetic anhydride (0.26 ml)was added thereto, and the mixture was warmed over 30 minutes to roomtemperature and stirred for 3 hours. The reaction mixture wasconcentrated under reduced pressure to give the title compound (550 mg,Y.:99%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.8 (3H, s), 3.9 (3H, s), 7.4 (1H, s), 8.2(1H, s).

ESI/MS (m/z):222 (M−H)⁻.

INTERMEDIATE EXAMPLE 64

4-Methoxy-2-trifluoromethylbenzothiazole-6-carboxylic acid

4-Amino-3-mercapto-5-methoxybenzoic acid (400 mg) was dissolved intetrahydrofuran (15 ml) and cooled to −78° C. Trifluoroacetic anhydride(0.31 ml) was added thereto, and the mixture was warmed over 30 minutesto room temperature and stirred for 30 minutes. The reaction mixture wasconcentrated under reduced pressure to give the title compound (550 mg,Y.:99%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):4.0 (3H, s), 7.6 (1H, s), 8.5 (1H, s).

INTERMEDIATE EXAMPLE 65

2-Methylbenzothiazole-6-carboxylic acid

4-Aminobenzoic acid (13 g) and ammonium thiocyanate (6.9 g) weresuspended in methanol (200 ml) and cooled at −15° C. on an ice bath. Amethanol solution (40 ml) containing bromine (4.7 ml) was added slowlydropwise thereto. The mixture was warmed to room temperature and stirredfor 2 hours, iced water (500 ml) was added thereto, and precipitatedcrystals were collected by filtration and washed with water andn-hexane. The product was dried under reduced pressure to give4-amino-3-thiocyanatobenzoic acid (9.4 g, Y.:53%) as white crystals.

¹H NMR; (DMSO-d₆) δ (ppm):6.6 (2H, brs), 6.8 (1H, d), 7.7 (1H, dd), 7.9(1H, d).

ESI/MS (m/z):193 (M−H)⁻.

Sodium sulfide (25 g) was suspended in water (60 ml) and ethanol (60ml), and after it was ascertained that the sodium sulfide had beendissolved at 40° C., the 4-amino-3-thiocyanatobenzoic acid (10 g)obtained above was added thereto. The solution was heated to 90° C. andstirred as such for 2 hours. The reaction mixture was cooled to roomtemperature, and 90% formic acid solution was added to the reactionmixture until it became acidic, and precipitated crystals were collectedby filtration and washed with water and n-hexane. The product was driedunder reduced pressure to give 4-amino-3-mercaptobenzoic acid (8.8 g,Y.:96%) as pale yellow crystals.

¹H NMR; (DMSO-d₆) δ (ppm):6.6 (2H, brs), 6.8 (1H, d), 7.7 (1H, dd), 7.9(1H, d).

ESI/MS (m/z):168 (M−H)⁻.

The 4-amino-3-mercaptobenzoic acid (170 mg) obtained above andthioacetamide (83 mg) were suspended in ethylene glycol (1.5 ml). Conc.hydrochloric acid (0.1 ml) was added thereto, and the mixture wasstirred for 7 hours at 100° C. The mixture was cooled to roomtemperature, then cold water was added thereto, and precipitatedcrystals were collected by filtration and washed with water andn-hexane. The product was dried under reduced pressure to give the titlecompound (150 mg, Y.:78%) as white crystals.

ESI/MS (m/z):192 (M−H)⁻.

INTERMEDIATE EXAMPLE 66

4-Methoxy-2-phenylbenzothiazole-6-carboxylic acid

4-Amino-3-mercapto-5-methoxybenzoic acid (600 mg) and thiobenzamide (450mg) were suspended in ethylene glycol (10 ml). Conc. hydrochloric acid(1.0 ml) was added thereto, and the mixture was stirred for 7 hours at60° C. The reaction mixture was cooled to room temperature, then coldwater was added thereto, and precipitated crystals were collected byfiltration and washed with water and n-hexane. The crystals were driedunder reduced pressure to give the title compound (280 mg, Y.:32%) aswhite crystals.

¹H NMR; (DMSO-d₆) δ (ppm):4.0 (3H, s), 7.5 (1H, d), 7.5-7.6 (3H, m),8.1-8.2 (2H, m), 8.3 (1H, d)

ESI/MS (m/z):284 (M−H)⁻.

INTERMEDIATE EXAMPLE 67

2-Phenylbenzothiazole-6-carboxylic acid

By the similar procedure as in Intermediate Example 66, the titlecompound (1.9 g, Y.:74%) was obtained from 4-amino-3-mercaptobenzoicacid (1.7 g).

ESI/MS (m/z):254 (M−H)⁻.

INTERMEDIATE EXAMPLE 68

2-Oxo-2,3-dihydrobenzothiazole-6-carboxylic acid

4-Amino-3-mercaptobenzoic acid (680 mg) was dissolved in tetrahydrofuran(20 ml), and potassium carbonate (550 mg) was added thereto and stirredfor 30 minutes at room temperature. The mixture was cooled to −78° C.,and triphosgene (400 mg) was added thereto and stirred for 1 hour. Themixture was warmed to room temperature and concentrated under reducedpressure until the volume of the solvent became ⅓. Water (20 ml) andformic acid were added to the concentrate until it became acidic, andprecipitated crystals were collected by filtration and washed with waterand n-hexane. The crystals were dried under reduced pressure to give thetitle compound (740 mg, Y.:95%) as white crystals.

1H NMR; (DMSO-d₆) δ (ppm):6.3 (1H, brs), 7.1 (1H, d), 7.8 (1H, d), 8.1(1H, s).

ESI/MS (m/z):194 (M−H)⁻.

INTERMEDIATE EXAMPLE 69

1-Methyl-1H-benzimidazole-5-carboxylic acid

Methyl 4-amino-3-nitrobenzoate (7.0 g), sodium hydroxide (5.7 g),potassium carbonate (4.9 g) and tetrabutylammonium bromide (0.22 g) weresuspended in toluene (100 ml). The mixture was stirred for 1 hour at 40°C., and then dimethylsulfuric acid (7.7 ml) was added thereto andstirred for 2 hours. The reaction solution was extracted with ethylacetate, and the extract was washed with water and dried over sodiumsulfate anhydrous. The product was concentrated under reduced pressureto give methyl 4-methylamino-3-nitrobenzoate (7.3 g, Y.:97%).

¹H NMR; (DMSO-d₆) δ (ppm):3.0 (d, 3H), 3.8 (s, 3H), 7.0 (d, 1H), 8.00(dd, 1H), 8.5-8.7 (brs, 1H), 8.6 (d, 1H).

ESI/MS (m/z):325 (M+H)⁺, 323 (M−H)⁻.

The methyl 4-methylamino-3-nitrobenzoate (6.3 g) obtained above wassuspended in 1,4-dioxane (125 ml). 20% Palladium hydroxide (6.3 g) wasadded thereto, and the mixture was stirred for 91 hours at roomtemperature in a hydrogen atmosphere. Insoluble matter was removed byfiltration, and the filtrate was concentrated under reduced pressure.The residue was purified by column chromatography (eluting solvent;ethyl acetate:n-hexane 1:4→2:3) to give methyl3-amino-4-methylaminobenzoate (3.3 g, Y.:62%).

ESI/MS (m/z):181 (M+H)⁺, 179 (M−H)⁻.

The methyl 3-amino-4-methylaminobenzoate (3.3 g) obtained above wasdissolved in formic acid (96 ml). Water (4 ml) was added thereto, andthe solution was stirred for 3 hours at 90° C. The reaction solution wasconcentrated under reduced pressure, and ethyl acetate was added to theresidue. The organic phase was washed with a saturated sodiumbicarbonate solution and dried over sodium sulfate anhydrous. Theproduct was concentrated under reduced pressure to give methyl1-methyl-1H-benzimidazole-5-carbonate (3.4 g, Y.:97%).

¹H NMR; (DMSO-d₆) δ (ppm):3.8 (s, 3H), 3.8 (s, 3H), 7.6 (d, 1H), 7.9(dd, 1H), 8.2 (d, 1H), 8.3 (s, 1H).

ESI/MS (m/z):191 (M+H)⁺.

The methyl 1-methyl-1H-benzimidazole-5-carbonate (500 mg) obtained abovewas dissolved in methanol (10 ml). 1 N Sodium hydroxide solution (8 ml)was added thereto, and the mixture was stirred for 4 hours at roomtemperature. Water was added to the reaction mixture which was thenacidified by formic acid. Precipitates were collected by filtration anddried under reduced pressure to give the title compound (367 mg,Y.:79%).

¹H NMR; (DMSO-d₆) δ (ppm):3.8 (s, 3H), 7.6 (d, 1H), 7.8 (dd, 1H), 8.2(d, 1H), 8.3 (s, 1H).

INTERMEDIATE EXAMPLE 70

2-Methylbenzoxazole-6-carboxylic acid

4-Amino-3-hydroxybenzoic acid (4.9 g) was added to acetic acid (250 ml)and stirred for 3 days at 130° C. The solution was concentrated underreduced pressure, and precipitates were collected by filtration. Theprecipitates were dissolved in methanol and chloroform. The solution wasconcentrated under reduced pressure, and precipitates were collected byfiltration, washed with methanol and dried under reduced pressure togive the title compound (3.5 g, Y.:62%).

¹H NMR; (DMSO-d₆) δ (ppm):2.6 (s, 3H), 7.7 (d, 1H), 7.9 (dd, 1H), 8.1(d, 1H).

ESI/MS (m/z):178 (M+H)⁺, 176 (M−H)⁻.

INTERMEDIATE EXAMPLE 71

5-Methyl-2,3-dihydro-1H-isoindole

Xylene (15 ml) was added to 4-methylphthalic anhydride (3.0 g) and urea(1.2 g), and the mixture was stirred overnight at 150° C. The reactionmixture was cooled to room temperature, and precipitated crystals werecollected by filtration and washed with ethanol and water. The crystalswere dried under reduced pressure to give 4-methylphthalimide (2.4 g,Y.:82%) as white crystals.

1H NMR; (CDCl₃) δ (ppm):2.5 (3H, s), 7.5 (1H, d), 7.6 (1H, s), 7.7 (1H,s).

The 4-methylphthalimide (1.8 g) obtained above was suspended intetrahydrofuran (3 ml), then 1 N borane tetrahydrofuran complex (30 ml)was added thereto at room temperature and stirred overnight at 60° C.The mixture was cooled to 0° C., then methanol (2.8 ml) and 6 Nhydrochloric acid (3.2 ml) were added thereto, and the mixture wasrefluxed for 1 hour. The reaction mixture was cooled to 0° C., then 6 Nsodium hydroxide solution was added thereto, and the reaction solutionwas extracted with ethyl acetate and then the extract was dried oversodium sulfate anhydrous. The resulting product was concentrated underreduced pressure, and the residue was purified by column chromatography(eluting solvent; dichloromethane→dichloromethane:methanol 10:1→5:1) togive the title compound (400 mg, Y.:27%).

¹H NMR; (CDCl₃) δ (ppm):2.3 (3H, s), 2.7 (1H, brs), 7.0 (1H, d), 7.1(1H, s), 7.2 (1H, d).

ESI/MS (m/z):134 (M+H)⁺.

In a similar procedure as employed in the Intermediate Example 71,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in Table 4. (Each symbolhas the same meaning as defined above.)

TABLE 4 Inter- mediate Example Compound Name ESI/MS(m/z) 725-fluoro-2,3-dihydro-1H-isoindole 138 (M + H)⁺ 735-bromo-2,3-dihydro-1H-isoindole 199 (M + H)⁺ 745-chloro-2,3-dihydro-1H-isoindole 155 (M + H)⁺ 755-t-butyl-2,3-dihydro-1H-isoindole 176 (M + H)⁺ 764-fluoro-2,3-dihydro-1H-isoindole 138 (M + H)⁺ 774-methyl-2,3-dihydro-1H-isoindole 134 (M + H)⁺ 784,7-dichloro-2,3-dihydro-1H-isoindole 189 (M + H)⁺ 794-hydroxy-2,3-dihydro-1H-isoindole 136 (M + H)⁺ 805-hydroxymethyl-2,3-dihydro-1H-isoindole 150 (M + H)⁺ 815-trifluoromethyl-2,3-dihydro-1H-isoindole 188 (M + H)⁺ 824,5,6,7-tetrachloro-2,3-dihydro-1H-isoindole 258 (M + H)⁺ 835,6-dichloro-2,3-dihydro-1H-isoindole 199 (M + H)⁺ 844-hydroxy-6-methyl-2,3-dihydro-1H- 150 (M + H)⁺ isoindole 854-methoxy-6-methyl-2,3-dihydro-1H- 164 (M + H)⁺ isoindole

INTERMEDIATE EXAMPLE 86

5-Methoxy-2,3-dihydro-1H-isoindole

3,4-Dimethylanisole (3.0 g) was added to carbon tetrachloride, andN-bromosuccinimide (7.9 g) and 2,2′-azobisisobutyronitrile (50 mg) wereadded thereto and refluxed overnight. The reaction mixture was cooled toroom temperature, insoluble matter was removed by filtration, and thefiltrate was concentrated under reduced pressure. The residue waspurified by column chromatography (eluting solvent; n-hexane:ethylacetate 25:1→20:1) to give 1,2-bisbromomethyl-4-methoxybenzene (1.2 g,Y.:19%).

1H NMR; (CDCl₃) δ (ppm):3.8 (3H, s), 4.6 (2H, s), 4.6 (2H, s), 6.8 (1H,dd), 6.9 (1H, d), 7.2 (1H, d).

Sodium hydride (0.35 g) was suspended in N,N-dimethylformamide (1.2 ml),and a solution of p-toluenesulfonamide (0.71 g) in N,N-dimethylformamide(2 ml) was added thereto and stirred for 30 minutes at room temperature.The mixture was stirred for 1 hour at 60° C., and a solution of the 1,2-bisbromomethyl-4-methoxybenzene (1.2 g) obtained above inN,N-dimethylformamide (2 ml) was added at 60° C. to the mixture. Themixture was stirred for 3 hours at room temperature, then ethyl acetatewas added thereto, and the reaction mixture was washed with water. Theorganic phase was dried over sodium sulfate anhydrous and concentratedunder reduced pressure to give the corresponding sulfonyl derivative.This product was mixed with phenol (0.54 g), n-propanol (0.72 ml) and48% hydrobromic acid (4.0 ml), and the mixture was stirred for 2 hoursat 100° C. The reaction mixture was cooled and then washed with ethylacetate. The aqueous phase was alkalinized, extracted with chloroform,and the extract was dried over sodium sulfate anhydrous. The product wasconcentrated under reduced pressure to give the title compound (89 mg,Y.:14%).

¹H NMR; (CDCl₃) δ (ppm):3.8 (3H, s), 4.1-4.2 (4H, m), 6.7-6.8 (2H, m),7.1-7.2 (1H, m).

INTERMEDIATE EXAMPLE 87

4-Methoxy-2,3-dihydro-1H-isoindole

From 3,4-dimethylanisole, 4-methoxy-2,3-dihydro-1H-isoindole wassynthesized by the similar procedure as in Intermediate Example 86.

H NMR; (CDCl₃) δ (ppm):3.8 (3H, s), 4.2-4.3 (4H, m), 6.7-7.2 (3H, m).

INTERMEDIATE EXAMPLE 88

2,3,4,5-Tetrahydro-1H-benzo[c]azepine

According to a method described in a literature (Tetrahedron, 1993, 49,1807-1820), the title compound (2.0 g, Y.:55%) was obtained from1-tetralone (3.3 ml).

ESI/MS (m/z):148 (M+H)⁺.

INTERMEDIATE EXAMPLE 89

3-Amino-1-(1,3-dihydroisoindol-2-yl)-3-methylbutan-1-one

2,3-Dihydro-1H-isoindole (543 mg) and 3-amino-3-methylbutanoic acid (700mg) were dissolved in N,N-dimethylformamide (30 ml).N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (876 mg)and hydroxybenzotriazole (698 mg) were added thereto at 0° C., and thenthe mixture was stirred overnight at room temperature. The reactionmixture was concentrated under reduced pressure, and water and ethylacetate were added to the residue. The organic phase was separated, andthe aqueous phase was adjusted to pH 9 by adding a saturated sodiumbicarbonate solution, and then extracted with ethyl acetate. The extractwas dried over sodium sulfate and concentrated under reduced pressure togive the title compound (0.60 g, Y.:60%) as a brown oily matter.

¹H NMR; (CDCl₃) δ (ppm):1.2 (6H, s), 2.4 (2H, s), 4.7-4.8 (4H, m),7.2-7.3 (4H, m).

ESI/MS (m/z):219 (M+H)⁺.

In a similar procedure as employed in the Intermediate Example 89,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in Tables 5 and 6. (Eachsymbol has the same meaning as defined above.)

TABLE 5 Inter- mediate Example Compound Name ESI/MS(m/z) 903-amino-3-methyl-1-(5-methyl-1,3- 233 (M + H)⁺dihydroisoindol-2-yl)butan-1-one 913-amino-1-(5-fluoro-1,3-dihydroisoindol-2- 237 (M + H)⁺yl)-3-methylbutan-1-one 92 3-amino-1-(5-bromo-1,3-dihydroisoindol-2- 298(M + H)⁺ yl)-3-methylbutan-1-one 933-amino-1-(5-chloro-1,3-dihydroisoindol-2- 254 (M + H)⁺yl)-3-methylbutan-1-one 94 3-amino-1-(5-t-butyl-1,3-dihydroisoindol- 275(M + H)⁺ 2-yl)-3-methylbutan-1-one 953-amino-1-(4-fluoro-1,3-dihydroisoindol-2- 237 (M + H)⁺yl)-3-methylbutan-1-one 96 3-amino-3-methyl-1-(4-methyl-1,3- 233 (M +H)⁺ dihydroisoindol-2-yl)butan-1-one 973-amino-1-(4,7-dichloro-1,3-dihydroisoindol- 288 (M + H)⁺2-yl)-3-methylbutan-1-one

TABLE 6 Intermediate Example Compound Name ESI/MS(m/z) 983-amino-1-(4-hydroxy-1,3- 235 (M + H)⁺dihydroisoindol-2-yl)-3-methylbutan-1-one 993-amino-1-(5-hydroxymethyl-1,3- 249 (M + H)⁺dihydroisoindol-2-yl)-3-methylbutan-1-one 1003-amino-3-methyl-1-(5-trifluoromethyl- 287 (M + H)⁺1,3-dihydroisoindol-2-yl)butan-1-one 1013-amino-3-methyl-1-(4,5,6,7-tetrachloro-1, 357 (M + H)⁺3-dihydroisoindol-2-yl)butan-1-one 102 3-amino-1-(5,6-dichloro-1,3- 288(M + H)⁺ dihydroisoindol-2-yl)-3-methylbutan-1-one 1033-amino-1-(4-hydroxy-6-methyl-1,3- 249 (M + H)⁺dihydroisoindol-2-yl)-3-methylbutan-1-one 1043-amino-1-(4-methoxy-6-methyl-1,3- 263 (M + H)⁺dihydroisoindol-2-yl)-3-methylbutan-1-one 105 3-amino-1-(5-methoxy-1,3-249 (M + H)⁺ dihydroisoindol-2-yl)-3-methylbutan-1-one 1063-amino-1-(4-methoxy-1,3- 249 (M + H)⁺dihydroisoindol-2-yl)-3-methylbutan-1-one 1073-amino-1-(3,4-dihydro-1H-isoquinolin- 233 (M + H)⁺2-yl)-3-methylbutan-1-one 108 2-amino-1-(1,3-dihydroisoindol-2-yl)-2-205 (M + H)⁺ methylpropan-1-one 109 2-amino-2-methyl-1-(1,3,4,5- 233(M + H)⁺ tetrahydrobenzo[c]azepin-2-yl)propan-1- one 1104-amino-1-(1,3-dihydroisoindol-2-yl)-4- 233 (M + H)⁺ methylpentan-1-one

INTERMEDIATE EXAMPLE 111

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid(2-amino-2-methylpropyl)amide

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid (0.18 g) wassuspended in dichloromethane (5 ml), and N,N-dimethylformamide (1 drop)was added thereto. The mixture was cooled to 0° C., and a solution ofoxalyl chloride (10 μl) in dichloromethane (3 ml) was added dropwisethereto over 10 minutes, and the mixture was stirred as such for 1 hourat 0° C. Thereafter, the mixture was stirred for 5 hours at roomtemperature to prepare the corresponding acid chloride.2-Amino-2-methylpropylamine (0.11 g) was dissolved in dichloromethane,and triethylamine (0.33 ml) was added thereto and cooled to −78° C. Theprepared acid chloride solution was added dropwise thereto over 30minutes and stirred as such for 30 minutes. The temperature of themixture was increased to room temperature, and the mixture was stirredfor 1 hour at room temperature. Water was added thereto, and the aqueousphase was acidified by 2 N hydrochloric acid. After washing withchloroform, the aqueous phase was alkalinized by 5 N sodium hydroxidesolution and extracted with chloroform. The organic phase was washedwith a saturated saline solution and dried over sodium sulfateanhydrous. The product was concentrated under reduced pressure to givethe title compound (0.14 g, Y.:56%) as yellow crystals.

ESI/MS (m/z):248 (M+H)⁺.

INTERMEDIATE EXAMPLE 112

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid(1-aminocyclopentylmethyl)amide

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid (0.31 g) wassuspended in tetrahydrofuran (7 ml), and N,N-dimethylformamide (0.04 ml)was added thereto. A solution of oxalyl chloride (200 μl) intetrahydrofuran (0.8 ml) was added dropwise thereto with ice cooling,and the mixture was stirred for 1 hour at the same temperature and thenstirred for 2 hours at room temperature. Potassium carbonate (0.54 g)was added thereto at −60° C. or less, and then a solution of1-(aminomethyl)cyclopentylamine (0.22 g) in tetrahydrofuran (0.8 ml) wasadded dropwise thereto. The mixture was stirred for 30 minutes at −60°C. or less and then stirred for 22 hours at room temperature. Water (6ml) was added thereto on an ice bath, and the reaction mixture wasadjusted to pH 2 by 6 N hydrochloric acid. The reaction mixture waswashed with chloroform, and the aqueous phase was adjusted to pH 12 by 5N sodium hydroxide solution and extracted with chloroform. The resultingproduct was washed with a saturated saline solution and then dried oversodium sulfate anhydrous. The product was concentrated under reducedpressure to give the title compound (57 mg, Y.:12%).

¹H NMR; (CDCl₃) δ (ppm):1.4-1.8 (8H, m), 2.5 (3H, s), 3.2-3.3 (2H, m),6.5, 8.8, 9.2 (3H, s).

ESI/MS (m/z):274 (M+H)⁺, 272 (M−H)⁻.

INTERMEDIATE EXAMPLE 113

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid(4-amino-4-methylpentyl)amide

2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid (177 mg) wassuspended in tetrahydrofuran (5 ml), and N,N-dimethylformamide (1 drop)was added thereto. Oxalyl chloride (100 μl) was added thereto with icecooling, and the mixture was stirred for 30 minutes at room temperature.The mixture was cooled again on ice, and 4-methyl-1,4-pentane<

>diamine (116 μl) and triethylamine (0.21 ml) were added thereto andstirred overnight at room temperature. By adding water and 2 Nhydrochloric acid, the reaction mixture was acidified, followed bywashing with chloroform. The aqueous phase was alkalinized by 5 N sodiumhydroxide solution, extracted with chloroform, and the extract was driedover sodium sulfate anhydrous. The product was concentrated underreduced pressure to give the title compound (151 mg, Y.:55%) as paleyellow crystals.

¹H NMR; (CDCl₃) δ (ppm):1.1 (6H, s), 1.7 (4H, m), 2.5 (3H, s), 3.4 (2H,dd), 6.5 (1H, s), 8.4 (1H, brs), 8.7 (1H, d), 9.1 (1H, d).

ESI/MS (m/z):276 (M+H)⁺, 274 (M−H)⁻.

INTERMEDIATE EXAMPLE 114

Methyl 2-amino-3-[(benzothiazole-6-carbonyl)amino]propionate

Benzothiazole-6-carboxylic acid (358 mg),N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (382 mg)and hydroxybenzotriazole (306 mg) were dissolved inN,N-dimethylformamide (10 ml) and stirred for 30 minutes with icecooling. A solution of methyl 3-amino-2-t-butoxycarbonylaminopropionate(560 mg) in N,N-dimethylformamide (8 ml) was added thereto, and themixture was stirred for 17 hours at a temperature ranging from icecooling to room temperature. The reaction mixture was concentrated underreduced pressure, and the organic phase was extracted by adding waterand ethyl acetate. The organic phase was washed with 10% citric acidsolution, 4% sodium bicarbonate solution and water, and dried oversodium sulfate anhydrous. The reaction product was concentrated underreduced pressure to give methyl3-[(benzothiazole-6-carbonyl)amino]-2-t-butoxycarbonylamino propionate(750 mg, Y.:98.8%).

The methyl 3-[(benzothiazole-6-carbonyl)amino]-2-t-butoxycarbonylaminopropionate (730 mg) obtained above was added to ice-cold trifluoroaceticacid (6ml) and stirred for 1 hour. The reaction mixture was concentratedunder reduced pressure, and ether was added to the concentrate undercooling on ice to precipitate crystals, and the crystals were collectedby filtration and dried under reduced pressure to give the titlecompound (817 mg, Y.: quant.).

ESI/MS (m/z):394 (M+H)⁺.

INTERMEDIATE EXAMPLE 115

3-Amino-1-(1,3-dihydroisoindol-2-yl)propan-1-one

N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (1.94 g)was added to a solution of 3-t-butoxycarbonylaminopropionic acid (1.90g) in N,N-dimethylformamide at 0° C. A solution of2,3-dihydro-1H-isoindole (1.00 g) in N,N-dimethylformamide was addedthereto. The mixture was warmed to room temperature and stirredovernight. The reaction mixture was concentrated under reduced pressure,and water and dichloromethane were added to the residue. The organicphase was separated and washed with 10% citric acid solution, 4% sodiumbicarbonate solution and a saturated saline solution. The product wasdried over sodium sulfate anhydrous and concentrated under reducedpressure. Ether was added to precipitate crystals, and the crystals werecollected by filtration and dried under reduced pressure to give t-butyl[3-(1,3-dihydroisoindole)-3-oxopropyl]carbamate (1.33 g, Y.:55%) as paleorange crystals.

The t-butyl [3-(1,3-dihydroisoindolyl)-3-oxopropyl]carbamate (1.33 g)obtained above was added to ice-cold trifluoroacetic acid (6 ml) andstirred as such for 30 minutes. The reaction solution was concentratedunder reduced pressure, and ether was added to the residue, andprecipitated crystals were collected by filtration and dried underreduced pressure to give the title compound (1.38 g, Y.:99%).

ESI/MS (m/z):191 (M+H)⁺.

In a similar procedure as employed in the Intermediate Example 115,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in in Table 7. (Each symbolhas the same meaning as defined above.)

TABLE 7 Inter- mediate Example Compound Name ESI/MS(m/z) 1163-amino-1-(3,4-dihydro-1H-isoquinolin-2-yl) 205 (M + H)⁺ propan-1-one117 3-amino-1-(2,3-dihydroindol-1-yl)propan-1- 191 (M + H)⁺ one 1184-amino-1-(1,3-dihydroisoindol-2-yl)butan- 205 (M + H)⁺ 1-one 1193-amino-N-benzothiazol-2-ylpropionamide 222 (M + H)⁺

INTERMEDIATE EXAMPLE 120

3-Amino-1-indol-1-ylpropan-1-one

The t-butyl [3-(2,3-dihydroindol-1-yl)-3-oxopropyl]carbamate (290 mg)obtained as the intermediate in Intermediate Example 117, and2,3-dichloro-5,6-dicyano-p-benzoquinone (510 mg) were suspended inchloroform (40 ml) and refluxed for 30 hours. The reaction mixture wascooled to room temperature, then insoluble matter was removed byfiltration, the filtrate was washed with water, and the organic phasewas dried over sodium sulfate anhydrous. The resulting product wasconcentrated under reduced pressure, and the residue was purified bycolumn chromatography (eluting solvent;dichloromethane→dichloromethane:methanol 10:1) to give t-butyl(3-indol-1-yl-3-oxopropyl)carbamate (270 mg, Y.:95%).

ESI/MS (m/z):289 (M+H)⁺, 287 (M−H)⁻.

The t-butyl (3-indol-1-yl-3-oxopropyl)carbamate (260 mg) obtained abovewas added to ice-cold trifluoroacetic acid (2.0 ml) and stirred as suchfor 1 hour. The product was concentrated under reduced pressure, thenether was added to the residue, and precipitated white crystals werecollected by filtration. The crystals were dried under reduced pressureto give a trifluoroacetate (260 g, Y.:94%) of the title compound.

¹H NMR; (DMSO-d₆) δ (ppm):3.2-3.3 (2H, m), 3.4 (2H, t), 6.8 (1H, d), 7.2(1H, t), 7.3 (1H, t), 7.6 (1H, d), 7.8 (3H, brs), 7.9 (1H, d), 8.3 (1H,d).

ESI/MS (m/z):189 (M+H)⁺, 187 (M−H)⁻.

INTERMEDIATE EXAMPLE 121

1,3-Dimethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid(2-aminoethyl)amide

Hydroxybenzotriazole (3.55 g) andN-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (4.45 g)were added to a solution of1,3-dimethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid (4.00 g) inN,N-dimethylformamide (40 ml) with ice cooling. The mixture was stirredfor 30 minutes at room temperature, and then t-butyl(2-aminoethyl)carbamate (3.65 ml) was added thereto and stirredovernight at room temperature. The reaction mixture was concentratedunder reduced pressure, and ethyl acetate and water were added to theresidue. The organic phase was washed with 10% citric acid solution, 4%sodium bicarbonate solution and a saturated saline solution. The productwas dried under sodium sulfate anhydrous and concentrated under reducedpressure to give t-butyl{2-[(1,3-dimethyl-1H-pyrazolo[3,4-b]pyridine-5-carbonyl)amino]ethyl}carbamate(4.02 g, Y.:57%) as colorless crystals.

¹H NMR; (DMSO-d₆) δ (ppm):1.4 (9H, s), 2.5 (3H, s), 3.4-3.6 (4H, m), 4.1(3H, s), 5.0, 7.5 (2H, brs), 8.4 (1H, s), 9.0 (1H, s).

The t-butyl{2-[(1,3-dimethyl-1H-pyrazolo[3,4-b]pyridine-5-carbonyl)amino]ethyl}carbamate(4.02 g) obtained above was added to ice-cold trifluoroacetic acid (20ml) and stirred as such for 2 hours. The reaction mixture wasconcentrated under reduced pressure, then ether was added thereto, andprecipitated crystals were collected by filtration. The product wasdried under reduced pressure to give the title compound (3.52 g, Y.:84%)as pale yellow crystals.

¹H NMR; (DMSO-d₆) δ (ppm):2.5 (3H, s), 3.0-3.1 (2H, m), 3.5-3.6 (2H, m),4.0 (3H, s), 7.8 (3H, brs), 8.7 (1H, s), 8.8 (1H, brt), 9.0 (1H, s).

In a similar procedure as employed in the Intermediate Example 121,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in Table 8. (Each symbolhas the same meaning as defined above.)

TABLE 8 Inter- mediate Example Compound Name ESI/MS(m/z) 122benzothiazole-6-carboxylic acid 222 (M + H)⁺ (2-aminoethyl)amide 1232-methylbenzothiazole-6-carboxylic acid 236 (M + H)⁺ (2-aminoethyl)amide124 5-methoxybenzothiazole-6-carboxylic acid 252 (M + H)⁺(2-aminoethyl)amide 125 4-methoxybenzothiazole-6-carboxylic acid 252(M + H)⁺ (2-aminoethyl)amide 126 2-phenylbenzothiazole-6-carboxylic acid298 (M + H)⁺ (2-aminoethyl)amide 127 benzothiazole-6-carboxylic acid 250(M + H)⁺ (4-aminobutyl)amide 128 1-methyl-1H-indole-2-carboxylic acid218 (M + H)⁺ (2-aminoethyl)amide 129 isoquinoline-3-carboxylic acid 216(M + H)⁺ (2-aminoethyl)amide 130 isoquinoline-1-carboxylic acid 216 (M +H)⁺ (2-aminoethyl)amide 131 quinoline-3-carboxylic acid 216 (M + H)⁺(2-aminoethyl)amide 132 quinoline-2-carboxylic acid 216 (M + H)⁺(2-aminoethyl)amide 133 5-oxo-2,3-dihydro-5H-thiazolo[3,2- 241 (M + H)⁺a]pyrimidine-6-carboxylic acid (2-aminoethyl)amide 1342,7-dimethylpyrazolo[1,5-a]pyrimidine-6- 234 (M + H)⁺ carboxylic acid(2-aminoethyl)amide 135 2,3-dihydrobenzo[1,4]dioxane-6-carboxylic 223(M + H)⁺ acid (2-aminoethyl)amide 1362-methylimidazo[1,2-a]pyridine-3-carboxylic 219 (M + H)⁺ acid(2-aminoethyl)amide 137 8-ethyl-5-oxo-2-pyrrolidin-1-yl-5,8- 331 (M +H)⁺ dihydropyrido [2,3-d]pyrimidine-6- carboxylic acid(2-aminoethyl)amide

INTERMEDIATE EXAMPLE 138

{t-Butoxycarbonyl-[2-(1,3-dihydroisoindol-2-yl)-2-oxoethyl]amino}aceticacid

Boc-imidine acetic acid (580 mg) was dissolved in N,N-dimethylformamide(3.5 ml), and N-(3-dimethylaminopropyl)-N′-ethylcarbodiimidehydrochloride (480 mg) was added thereto and stirred for 1 hour at roomtemperature. 2,3-Dihydro-1H-isoindole (280 μl) was added thereto, andthe mixture was stirred overnight at room temperature. The mixture wasconcentrated under reduced pressure, and 10% citric acid solution andethyl acetate were added to the residue. The organic phase wasseparated, then washed with 4% sodium bicarbonate solution and asaturated saline solution, and dried over sodium sulfate anhydrous. Theproduct was concentrated under reduced pressure, and the residue waspurified by column chromatography (eluting solvent;dichloromethane:methanol 20:1→10:1) to give the title compound (270 mg,Y.:33%).

¹H NMR; (DMSO-d₆) δ (ppm):1.4 (9H, s), 3.9 (2H, s), 4.2 (2H, s), 4.8(4H, d), 7.2-7.3 (4H, m).

ESI/MS (m/z):335 (M+H)⁺, 333 (M−H)⁻.

In a similar procedure as employed in the Intermediate Example 138,compounds were synthesized according to the following reaction scheme.The synthesized compounds and data are shown in Table 9. (Each symbolhas the same meaning as defined above. )

TABLE 9 Intermediate Example Compound Name ESI/MS(m/z) 139{t-butoxycarbonyl-[2-(2,3-dihydroindol- 335 (M + H)⁺1-yl)-2-oxoethyl]amino}-acetic acid 336 (M − H)⁻ 140{t-butoxycarbonyl-[2-(3,4-dihydro-1H-isoquinolin- 349 (M + H)⁺2-yl)-2-oxoethyl]amino}- 347 (M − H)⁻ acetic acid 141{t-butoxycarbonyl-[2-(3,4-dihydro-2H-quinolin- 349 (M + H)⁺1-yl)-2-oxoethyl]amino}-acetic 347 (M − H)⁻ acid 142{t-butoxycarbonyl(isoquinolin-3-ylcarbonylmethyl) 360 (M + H)⁺amino}acetic acid 358 (M − H)⁻ 143[t-butoxycarbonyl(quinolin-2-ylcarbonylmethyl) 360 (M + H)⁺ amino]aceticacid 358 (M − H)⁻ 144 {t-butoxycarbonyl-[(2-methylquinolin-4- 374 (M +H)⁺ ylcarbonyl)methyl]amino}acetic acid 372 (M − H)⁻ 145{t-butoxycarbonyl-[(3-methylcinnolin-5- 375 (M + H)⁺ylcarbonyl)methyl]amino}acetic acid 373 (M − H)⁻ 146{t-butoxycarbonyl-[(4-methyl-2-oxo-2H- 391 (M + H)⁺chromen-7-ylcarbonyl)methyl]amino}- 389 (M − H)⁻ acetic acid 147[(benzothiazol-2-ylcarbonylmethyl)-t-butoxycarbonylamino] 366 (M + H)⁺acetic acid 364 (M − H)⁻ 148 {t-butoxycarbonyl-[(9H-purin-6-ylcarbonyl)351 (M + H)⁺ methyl]amino}acetic acid 349 (M − H)⁻ 149{t-butoxycarbonyl-[(2-methylsulfanyl[1, 397 (M + H)⁺2,4]triazolo[1,5-a]pyrimidin-7-ylcarbonyl) 395 (M − H)⁻methyl]amino}acetic acid 150 {t-butoxycarbonyl-[2-(octahydroquinolin-355 (M + H)⁺ 1-yl)-2-oxoethyl]amino}acetic acid 353 (M − H)⁻

EXAMPLE 1

(S)-2,7-Dimethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid{2-[(2-cyanopyrrolidin-1-yl)-2-oxoethylamino]-2-methylpropy l}amide

N,N′-Carbonyldiimidazole (930 mg) was added to a solution of2,7-dimethylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid (1.00 g) intetrahydrofuran (30 ml), and the mixture was stirred for4 hours at roomtemperature. The reaction mixture was added slowly dropwise to asolution of(S)-1-[(2-amino-1,1-dimethylethyl)aminoacetyl]pyrrolidine-2-carbonitriledihydrochloride (1.56 g) and triethylamine (3.6 ml) in tetrahydrofuran(30 ml) with ice cooling. The mixture was warmed to room temperature andstirred overnight. The reaction mixture was concentrated under reducedpressure, and dichloromethane was added to the residue. Insoluble matterwas removed by filtration, and the filtrate was concentrated underreduced pressure. The residue was purified by column chromatography(eluting solvent; dichloromethane:methanol 50:1) to give the titlecompound (690 mg, Y.:33%). 4N Hydrochloric acid/1,4-dioxane (0.50 ml)was added to a solution of the resulting compound (690 mg) in1,4-dioxane (5.0 ml) at 10° C. and stirred for 10 minutes. Crystals wereprecipitated by adding ether and then collected by filtration. Thecrystals were dried under reduced pressure to give a hydrochloride (670mg, Y.:90%) of the title compound as yellow crystals.

¹H NMR; (DMSO-d₆) δ (ppm):1.37 (6H, s), 2.05-2.31 (4H, m), 2.47 (3H, s),2.87 (3H, s), 3.30-3.80 (4H, m), 4.10-4.30 (2H, m), 4.84-4.86 (1H, m),6.60 (1H, s), 8.68 (1H, s), 8.93-8.97 (3H, m).

In a similar procedure as employed in the Example 1, compounds weresynthesized according to the following reaction scheme. The synthesizedcompounds and data are shown in Tables 10 to 17.

TABLE 10 Example A ESI/MS(m/z) ¹H NMR 2 2-methylpyrazolo- 384(M+H)⁺(DMSO-d₆)δ(ppm): 1.36(6H, s), 2.00-2.30(4H, [1,5-a]pyrimidin- 382(M−H)⁻m), 2.50(3H, s), 3.30-3.80(4H, m), 6-yl 4.10-4.30(2H, m), 4.80(1H, m),6.63(1H, s), 8.80-8.90(3H, m), 9.50(1H, s). 3 2,5,7-trimethyl- 412(M+H)⁺(DMSO-d₆)δ(ppm): 1.37(6H, s), 1.98-2.09(2H, pyrazolo[1,5-a]- 410(M−H)⁻m), 2.18-2.27(2H, m), 2.43(3H, s), 2.47(3H, pyrimidin-6-yl s), 2.66(3H,s), 3.52-3.63(1H, m), 3.62(2H, d), 3.71-3.76(1H, m), 4.10-4.21(2H, m),4.86(1H, dd), 6.44(1H, s), 8.92(1H, brt), 9.12(2H, brs). 47-methoxy-2,5-di- 428(M+H)⁺ (DMSO-d₆)δ(ppm): 1.34(6H, s), 1.97-2.08(2H,methylpyrazolo[1, 426(M−H)⁻ m), 2.15-2.22(2H, m), 2.31(3H, s), 2.45(3H,5-a]pyrimidin-6- s), 3.17(3H, s), 3.48-3.57(3H, m), yl 3.70-3.75(1H, m),4.02-4.09(2H, m), 4.86(1H, dd), 6.30(1H, s), 8.68(1H, brt),9.00-9.06(2H, m).

TABLE 11 Example A ESI/MS(m/z) ¹H NMR 5 5,7-dimethyl-2- 474(M+H)⁺(DMSO-d₆)δ(ppm): 1.38(6H, s), 2.02-2.10(2H, phenylpyrazolo[1, 472(M−H)⁻m), 2.19-2.25(2H, m), 2.52(3H, s), 2.75(3H, 5-a]pyrimidin-6- s)3.53-3.76(4H, m), 4.11(1H, dd), 4.18(1H, yl dd), 4.87(1H, dd), 7.18(1H,s), 7.44(1H, t), 7.51(2H, dd), 8.07(2H, d) 8.94(1H, t), 9.10(2H, brs). 62-methyl-7-tri- 440(M+H)⁺ (DMSO-d₆)δ(ppm): 1.37(6H, s), 2.02-2.10(2H,fluoromethyl- 438(M−H)⁻ m), 2.19-2.24(2H, m), 2.53(3H, s),pyrazolo[1,5-a]- 3.49-3.62(3H, m), 3.69-3.74(1H, m), 4.13-4.16(2H, m),pyrimidin-6-yl 4.86(1H, dd), 6.94(1H, s), 9.00(2H, brs), 9.09(1H, t),9.77(1H, s). 7 2-t-butyl-5,7-di- 454(M+H)⁺ (DMSO-d₆)δ(ppm): 1.36(15H,s), methylpyrazolo[1,5- 452(M−H)⁻ 2.01-2.10(2H, m), 2.19-2.24(2H, m),2.47(3H, s), a]pyrimidin-6-yl 2.66(3H, s) 3.51-3.71(4H, m),4.11-4.19(2H, m), 4.87(1H, dd), 6.52(1H, s), 8.80(1H, t), 9.08(2H, brs).8 2-t-butyl-7- 440(M+H)⁺ (DMSO-d₆)δ(ppm): 1.36(6H, s), 1.38(9H, s),methylpyrazolo[1,5- 438(M−H)⁻ 1.97-2.08(2H, m), 2.19-2.25(2H, m),a]pyrimidin-6-yl 2.88(3H, s), 3.51-3.58(3H, m), 3.70-3.76(1H, m),4.12-4.17(2H, m), 4.87(1H, dd), 6.73(1H, s), 8.68(1H, s), 8.91(1H, t),8.95(2H, brs). 9 7-methyl-2-phenyl- 460(M+H)⁺ (DMSO-d₆)δ(ppm): 1.39(6H,s), 2.03-2.11(2H, pyrazolo[1,5-a]- 458(M−H)⁻ m), 2.19-2.25(2H, m),2.96(3H, s), pyrimidin-6-yl 3.54-3.69(4H, m), 4.11-4.23(2H, m) 4.88(1H,dd), 7.36(1H, s), 7.47(1H, t), 7.52(2H, dd), 8.10(2H, d) 8.77(1H, s),9.01-9.06(3H, m). 10 7-methoxy-5- 490(M+H)⁺ (DMSO-d₆)δ(ppm): 1.36(6H,s), 2.01-2.09(2H, methyl-2-phenyl- 488(M−H)⁻ m), 2.19-2.28(2H, m),2.48(3H, s), pyrazolo[1,5-a]- 3.52-3.58(3H, m), 3.71-3.73(1H, m),3.77(3H, s), pyrimidin-6-yl 4.87(1H, dd), 7.09(1H, s), 7.45(1H, t),7.51(2H, t), 7.98(2H, d) 8.69(1H, t), 8.97-9.01(2H, m). 11 5-hydroxy-2-400(M+H)⁺ (DMSO-d₆)δ(ppm): 1.31(6H, s), 2.05-2.27(4H,methylpyrazolo[1,5- 398(M−H)⁻ m), 2.32(3H, s), 3.52-3.68(5H, m),a]pyrimidin-6-yl 3.96-4.08(2H, m), 4.82-4.85(1H, m), 6.15(1H, s),8.55(1H, s), 9.36(1H, brt). 12 7-hydroxy-2- 400(M+H)⁺ (DMSO-d₆)δ(ppm):1.22(6H, s), 2.05-2.27(4H, methylpyrazolo[1,5- 398(M−H)⁻ m), 2.28(3H,s), 3.48-3.53(4H, m), a]pyrimidin-6-yl 3.63-3.69(1H, m), 3.79-3.89(2H,m), 4.79-4.82(1H, m), 5.97(1H, s), 8.47(1H, s), 9.65(1H, brt).

TABLE 12 Example A ESI/MS(m/z) ¹H NMR 13 2-hydroxymethyl- 400(M+H)⁺(DMSO-d₆)δ(ppm): 1.05(6H, s), 1.96-2.23(4H, pyrazolo[1,5-a]- 398(M−H)⁻m), 3.16-3.51(5H, m), 3.60-3.66(1H, m), pyrimidin-6-yl 4.68(2H, s),4.72-4.75(1H, m), 5.39(1H, brs), 6.71(1H, s), 8.44(1H, brt), 8.87(1H,d), 9.44(1H, d). 14 2-methoxymethyl- 414(M+H)⁺ (DMSO-d₆)δ(ppm): 1.35(6H,s), 1.98-2.29(4H, pyrazolo[1,5-a]- 412(M−H)⁻ m), 3.36(3H, s),3.57-4.15(6H, m), 4.63(2H, pyrimidin-6-yl s), 4.82-4.85(1H, m), 6.77(1H,s), 8.94(1H, d), 9.11(1H, brt), 9.68(1H, d). 15 1H-indol-3-yl 368(M+H)⁺(DMSO-d₆)δ(ppm): 1.04(6H, s), 1.90-2.20(4H, 366(M−H)⁻ m), 3.15-3.30(2H,m), 3.35-3.50(3H, m), 3.60-3.70(1H, m), 4.74(1H, q), 7.05-7.20(2H, m),7.42(1H, d), 7.66(1H, brs), 8.05(1H, d), 8.10(1H, d), 11.56(1H, s). 161H-indol-5-yl 368(M+H)⁺ (DMSO-d₆)δ(ppm): 1.33, 1.34(6H, 2s), 366(M−H)⁻2.00-2.30(4H, m), 3.50-3.60(3H, m), 3.70-3.80(1H, m), 4.05-4.25(2H, m),4.87(1H, q), 6.55(1H, s), 7.45(2H, t), 7.68(1H, dd), 8.21(1H, s),8.59(1H, brt), 8.92(2H, brs), 11.43(1H, s). 17 1-methyl-1H-indol-382(M+H)⁺ (DMSO-d₆)δ(ppm): 1.34(6H, s), 1.95-2.15(2H, 2-yl 380(M−H)⁻ m),2.15-2.30(2H, m), 3.45-3.65(3H, m), 3.70-3.80(1H, m), 3.98(3H, s),4.00-4.25(2H, m), 4.87(1H, m), 7.12(1H, t), 7.24(1H, s), 7.29(1H, t),7.54(1H, d), 7.66(1H, d), 8.73(1H, brs), 8.91(2H, brs). 181-methyl-1H-indol- 382(M+H)⁺ (DMSO-d₆)δ(ppm): 1.33(6H, s), 2.00-2.24(4H,3-yl 380(M−H)⁻ m), 3.53-3.57(5H, m), 3.67-3.75(1H, m), 3.85(3H, s),4.12(1H, ddd), 4.16(1H, ddd), 4.86(1H, dd), 7.17(1H, dd), 7.24(1H, dd),7.51(1H, d), 8.13(1H, d), 8.15(1H, s), 8.25(1H, t), 8.94(2H, brs). 191-methyl-1H-indol- 382(M+H)⁺ (DMSO-d₆)δ(ppm): 1.35(6H, s), 2.00-2.30(4H,4-yl 380(M−H)⁻ m), 3.50-3.65(3H, m), 3.65-3.80(1H, m), 3.83(3H, s),4.00-4.25(2H, m), 4.86(1H, q), 6.84(1H, d), 7.24(1H, t), 7.44(1H, d),7.57(1H, d), 7.64(1H, d), 8.51(1H, brt), 8.93(2H, brs). 201-methyl-1H-indol- 382(M+H)⁺ (DMSO-d₆)δ(ppm): 1.34(6H, s), 1.90-2.30(4H,5-yl 380(M−H)⁻ m), 3.20-3.45(2H, m), 3.45-3.65(2H, m), 3.70-3.80(1H, m),3.83(3H, s), 4.00-4.25(2H, m), 4.87(1H, q), 6.55(1H, d), 7.43(1H, d),7.51(1H, d), 7.73(1H, d), 8.20(1H, s), 8.59(1H, brs), 8.89(2H, brs).

TABLE 13 Example A ESI/MS(m/z) ¹H NMR 21 1-methyl-1H-indol- 382(M+H)⁺(DMSO-d₆)δ(ppm): 1.34(6H, s), 2.00-2.25(4H, 6-yl 380(M−H)⁻ m),3.50-3.60(3H, m), 3.65-3.80(1H, m), 3.86(3H, s), 4.05-4.25(2H, m),4.87(1H, q), 6.48(1H, d), 7.52(1H, d), 7.62(2H, s), 8.06(1H, s),8.63(1H, brt), 8.80-9.00(2H, brs). 22 1-methyl-1H-indol- 382(M+H)⁺(DMSO-d₆)δ(ppm): 1.37(6H, s), 1.95-2.15(2H, 7-yl 380(M−H)⁻ m),2.15-2.30(2H, m), 3.50-3.65(3H, m), 3.65-3.80(1H, m), 3.76(3H, s),4.05-4.25(2H, m), 4.86(1H, m), 6.51(1H, d), 7.08(1H, dd), 7.33(1H, d),7.36(1H, d), 7.67(1H, d), 8.71(1H, brs), 8.95(1H, brs). 23 4-methoxy-1-412(M+H)⁺ (DMSO-d₆)δ(ppm): 1.33(6H, s), 2.00-2.15(2H, methyl-1H-indol-2-410(M−H)⁻ m), 2.15-2.30(2H, m), 3.50-3.60(3H, m), 3.70-3.80(1H, m),3.90(3H, s), 3.96(3H, s), 4.05-4.25(2H, m), 4.88(1H, m), 6.60(1H, d),7.12(1H, d), 7.22(1H, t), 7.34(1H, s), 8.63(1H, brt), 8.92(2H, brs). 246-methoxy-1- 412(M+H)⁺ (DMSO-d₆)δ(ppm): 1.32(6H, s), 2.00-2.15(2H,methyl-1H-indol-2- 410(M−H)⁻ m), 2.15-2.30(2H, m), 3.45-3.60(3H, m), yl3.70-3.80(1H, m), 3.83(3H, s), 3.95(3H, s), 4.00-4.25(2H, m), 4.87(1H,m), 6.75(1H, d), 7.02(1H, s), 7.18(1H, s), 7.53(1H, d), 8.60(1H, s),8.90(2H, brs). 25 4,6-dimethoxy-1- 442(M+H)⁺ (DMSO-d₆)δ(ppm): 1.32(6H,s), 1.95-2.15(2H, methyl-1H-indol- 440(M−H)⁻ m), 2.15-2.30(2H, m),3.45-3.60(3H, m), 2-yl 3.70-3.80(1H, m), 3.82(3H, s), 3.86(3H, s),3.92(3H, s), 4.00-4.25(2H, m), 4.87(1H, m), 6.24(1H, s), 6.62(1H, s),7.27(1H, s), 8.49(1H, brt), 8.88(2H, brs). 26 5-methoxy-1,2- 426(M+H)⁺(DMSO-d₆)δ(ppm): 1.40(6H, s), 2.00-2.30(4H, dimethyl-1H- m), 2.62(3H,s), 3.30-3.80(4H, m), 3.68(3H, indol-3-yl s), 3.80(3H, s), 4.83-3.86(1H,m), 6.83(1H, dd), 7.32(1H, d), 7.40(1H, d), 7.80(1H, brs), 8.80-9.00(2H,m). 27 5-methoxy-1- 412(M+H)⁺ (DMSO-d₆)δ(ppm): 1.31(6H, s),2.00-2.15(2H, methyl-1H-indol-3- 410(M−H)⁻ m), 2.15-2.30(2H, m),3.50-3.60(3H, m), 3.70-3.80(1H, m), 3.77(3H, s), 3.82(3H, s),4.05-4.25(2H, m), 4.86(1H, m), 6.87(1H, dd), 7.42(1H, d), 7.64(1H, d),8.05(1H, s), 8.14(1H, brt), 8.89(2H, brs). 28 7-methoxy-1- 412(M+H)⁺(DMSO-d₆)δ(ppm): 1.33(6H, s), 2.00-2.15(2H, methyl-1H-indol-5- 410(M−H)⁻m), 2.15-2.30(2H, m), 3.50-3.60(3H, m), yl 3.70-3.80(1H, m), 3.94(3H,s), 4.02(3H, s), 4.00-4.25(2H, m), 4.87(1H, m), 6.49(1H, d), 7.19(1H,s), 7.30(1H, d), 7.82(1H, s), 8.64(1H, brt), 8.93(2H, brs).

TABLE 14 Example A ESI/MS(m/z) ¹H NMR 29 1-(2,2-dimethyl- 438(M+H)⁺(CDCl₃)δ(ppm): 1.02(9H, s), 1.18(6H, s), propyl)-1H-indol- 436(M−H)⁻2.12-2.29(4H, m), 3.36-3.47(6H, m), 3-yl 3.57-3.70(1H, m), 3.94(2H, s),4.68-4.73(1H, m), 6.94-7.05(1H, m), 7.23-7.25(1H, m), 7.37-7.39(1H, m),7.79(1H, s), 8.10-8.13(1H, m). 30 1-isobutyl-1H- 424(M+H)⁺(CDCl₃)δ(ppm): 0.94(6H, d), 1.19(6H, s), indol-3-yl 422(M−H)⁻2.10-2.29(5H, m), 3.37-3.48(6H, m), 3.58-3.62(1H, m), 3.93(2H, d),4.67-4.75(1H, m), 6.87-6.97(1H, m), 7.25-7.27(1H, m), 7.35-7.37(1H, m),7.78(1H, s), 8.11-8.13(1H, m). 31 1-(2,2-dimethyl- 438(M+H)⁺(DMSO-d₆)δ(ppm): 0.93(9H, s), 1.35(6H, s), propyl)-1H-indol- 436(M−H)⁻1.98-2.29(4H, m), 3.54-3.62(5H, m), 5-yl 3.71-3.74(1H, m), 4.03(2H, d),4.07-4.19(2H, m), 4.84-4.86(1H, m), 6.56(1H, d), 7.38(1H, d), 7.58(1H,d), 7.72(1H, dd), 8.20(1H, d), 8.59(1H, brt), 8.94(1H, brs). 321-isobutyl-1H- 424(M+H)⁺ (DMSO-d₆)δ(ppm): 0.84(6H, d), 1.35(6H, s),indol-5-yl 422(M−H)⁻ 1.98-2.29(5H, m), 3.54-3.65(6H, m), 3.71-3.74(1H,m), 4.02(2H, d), 4.07-4.19(2H, m), 4.84-4.86(1H, m), 6.56(1H, d),7.44(1H, d), 7.55(1H, d), 7.73(1H, dd), 8.22(1H, s), 8.59(1H, brt),8.96(1H, brs). 33 1-benzyloxymethyl- 488(M+H)⁺ (DMSO-d₆)δ(ppm): 1.33,1.34(6H, 2s), 1H-indol-3-yl 486(M−H)⁻ 1.95-2.15(2H, m), 2.15-2.30(2H,m), 3.50-3.60(3H, m), 3.70-3.80(1H, m), 4.05-4.25(2H, m), 4.50(2H, s),4.87(1H, m), 5.74(2H, s), 7.15-7.40(7H, m), 7.65(1H, d), 8.17(1H, d),8.33(1H, s), 8.40(1H, brt), 8.93(2H, brs). 34 1-methoxymethyl- 412(M+H)⁺(DMSO-d₆)δ(ppm): 1.04, 1.05(6H, 2s), 1H-indol-3-yl 410(M−H)⁻1.95-2.10(2H, m), 2.10-2.20(2H, m), 3.15-3.35(3H, m), 3.35-3.50(2H, m),3.60-3.70(1H, m), 4.74(1H, m), 5.57(2H, s), 7.15-7.25(2H, m), 7.60(1H,d), 7.79(1H, brt), 8.13(1H, d). 35 1-acetoxymethyl- 440(M+H)⁺(DMSO-d₆)δ(ppm): 1.04(6H, s), 1.95-2.10(2H, 1H-indol-3-yl 438(M−H)⁻ m),2.04(3H, s), 2.10-2.20(2H, m), 3.15-3.30(2H, m), 3.35-3.50(3H, m),3.60-3.70(1H, m), 4.74(1H, m), 6.20(2H, s), 7.20(1H, t), 7.27(1H, t),7.63(1H, d), 7.85(1H, brt), 8.13(1H, d), 8.19(1H, s). 361-benzyloxymethyl- 488(M+H)⁺ (DMSO-d₆)δ(ppm): 1.05(6H, s), 1.95-2.06(2H,1H-indol-5-yl 486(M−H)⁻ m), 2.11-2.21(2H, m), 3.20-3.30(2H, m),3.36-3.56(3H, m), 3.60-3.70(1H, m), 4.45(2H, s), 4.74-4.77(1H, m),5.71(2H, s).

TABLE 15 Example A ESI/MS(m/z) ¹H NMR 37 hydroxymethyl- 398(M+H)⁺(DMSO-d₆)δ(ppm): 1.03, 1.04(6H, 2s), 1H-indol-5-yl 1.95-2.20(4H, m),3.20-3.30(2H, m), 3.40-3.60(3H, m), 3.60-3.70(1H, m), 4.75(1H, q),5.53(2H, d), 6.51(1H, t), 6.55(1H, d), 7.48(1H, d), 7.59(1H, d),7.70(1H, dd), 8.10-8.20(1H, m), 8.13(1H, d). 38 methoxymethyl- 412(M+H)⁺(DMSO-d₆)δ(ppm): 1.03, 1.04(6H, 2s), 1H-indol-5-yl 410(M−H)⁻1.95-2.20(4H, m), 3.15(3H, s), 3.20-3.30(2H, m), 3.30-3.50(4H, m),3.60-3.70(1H, m), 4.75(1H, q), 5.56(2H, s), 6.61(1H, d), 7.57(1H, d),7.61(1H, d), 7.70(1H, dd), 8.14(1H, d), 8.20-8.30(1H, m). 391-(2,2-dimethyl- 468(M+H)⁺ (DMSO-d₆)δ(ppm): 0.95(9H, s), 1.33(6H, s),propyl)-5-methoxy- 466(M−H)⁻ 1.95-2.15(2H, m), 2.15-2.25(2H, m),1H-indol-3-yl 3.50-3.60(3H, m), 3.70-3.80(1H, m), 3.77(3H, s), 3.99(2H,s), 4.05-4.25(2H, m), 4.87(1H, m), 6.83(1H, dd), 7.51(1H, d), 7.67(1H,d), 8.07(1H, s), 8.33(1H, brt), 8.88(2H, brs). 40 1-(2,2-dimethyl-452(M+H)⁺ (DMSO-d₆)δ(ppm): 0.95(9H, s), 1.32, propyl)-5-methyl-450(M−H)⁻ 1.33(6H, 2s), 2.00-2.15(2H, m), 2.15-2.25(2H, 1H-indol-3-ylm), 2.39(3H, s), 3.50-3.60(3H, m), 3.70-3.80(1H, m), 4.00(2H, s),4.05-4.25(2H m), 4.87(1H, m), 7.02(1H, d), 7.48(1H, d), 7.94(1H, s),8.07(1H, s), 8.26(1H, brt), 8.92(2H, brs) 41 1-(2,2-dimethyl- 454(M+H)⁺(DMSO-d₆)δ(ppm): 0.94(9H, s), 1.31, propyl)-5-hydroxy- 452(M−H)⁻1.32(6H, 2s), 1.95-2.15(2H, m), 2.15-2.25(2H, 1H-indol-3-yl m),3.45-3.60(3H, m), 3.65-3.75(1H, m), 3.94(2H, s), 4.00-4.20(2H, m),4.86(1H, m), 6.68(1H, dd), 7.37(1H, d), 7.52(1H, d), 8.00(1H, s),8.16(1H, brt), 8.93(2H, brs). 42 1-(2,2-dimethyl- 482(M+H)⁺(DMSO-d₆)δ(ppm): 1.10(6H, s), 1.16(9H, s), propionyloxy- 2.10-2.30(4H,m), 3.30-3.50(5H, m), methyl)-1H-indol- 3.70-3.80(1H, m), 4.79-4.81(1H,m), 6.30(2H, s), 3-yl 7.24-7.34(2H, m), 7.66-7.67(1H, m), 7.84(1H, brs),8.19-8.21(1H, m), 8.24(1H, s). 43 1-t-butoxy- 482(M+H)⁺ (DMSO-d₆)δ(ppm):1.10(6H, s), 1.43(9H, s), carbonylmethyl-1H- 2.00-2.20(4H, m),3.20-3.30(2H, m), indol-5-yl 3.40-3.50(3H, m), 3.60 3.70(1H, m),5.00(2H, s), 6.57(1H, d), 7.40(2H, m), 7.67(1H, dd), 8.06(1H, brs),8.13(1H, d). 44 methyl-2,3-dihydro- 384(M+H)⁺ (DMSO-d₆)δ(ppm): 1.29(6H,s), 1.95-2.15(2H, 1H-indol-5- 382(M−H)⁻ m), 2.15-2.30(2H, m), 2.77(3H,s), 2.93(2H, yl t), 3.38(2H, t), 3.45-3.60(3H, m), 3.70-3.80(1H, m),4.00-4.20(2H, m), 4.86(1H, m), 6.50(1H, d), 7.61(1H, s), 7.66(1H, d),8.35(1H, brt), 8.83(2H, brs).

TABLE 16 Example A ESI/MS(m/z) ¹H NMR 45 1-acetyl-1H-indol- 410(M+H)⁺(DMSO-d₆)δ(ppm): 1.36(6H, s), 2.00-2.30(4H, 3-yl 408(M−H)⁻ m), 2.72(3H,s), 3.50-3.70(3H, m), 3.70-3.85(1H, m), 4.10-4.30(2H, m), 4.88(1H, m),7.30-7.50(2H, m), 8.19(1H, d), 8.34(1H, d), 8.70-8.80(1H, m), 8.80(1H,s), 8.95(2H, brs). 46 1-acetyl-2,3-di- 412(M+H)⁺ (DMSO-d₆)δ(ppm):1.31(6h, s), 2.00-2.30(4H, hydro-1H-indol-5- 410(M−H)⁻ m), 2.19(3H, s),3.19(2H, t), 3.50-3.60(3H, yl m), 3.65-3.75(1H, m), 4.05-4.20(2H, m),4.15(2H, t), 4.86(1H, q), 7.75(1H, d), 7.78(1H, s), 8.07(1H, d),8.58(1H, t), 8.75-9.00(2H, m). 47 1-acetyl-1H-indol- 410(M+H)⁺(DMSO-d₆)δ(ppm): 1.35(6H, s), 2.00-2.15(2H, 5-yl 408(M−H)⁻ m),2.15-2.30(2H, m), 2.68(3H, s), 3.50-3.65(3H, m), 3.70-3.80(1H, m),4.05-4.30(2H, m), 4.87(1H, m), 6.87(1H, d), 7.89(1H, d), 7.97(1H, d),8.23(1H, s), 8.39(1H, d), 8.77(1H, brs), 8.91(2H, brs). 48 1-benzoyl-1H-472(M+H)⁺ (DMSO-d₆)δ(ppm): 1.10(6H, m), 2.00-2.20(4H, indol-5-yl470(M−H)⁻ m), 3.20-3.50(5H, m), 3.60-3.70(1H, m), 4.75-4.76(1H, m),6.86(1H, d), 7.47-7.53(2H, m), 7.61-7.64(2H, m), 7.70-7.74(1H, m),7.78(1H, d), 7.84-7.90(2H, m), 8.21(1H, brs), 8.28(1H, d). 491-(2,2-dimethyl- 452(M+H)⁺ (DMSO-d₆)δ(ppm): 1.10(6H, s), 1.50(9H, s),propionyl)-1H- 2.00-2.20(4H, m), 3.20-3.50(5H, m), indol-5-yl3.60-3.70(1H, m), 4.75-7.77(1H, m), 6.84(1H, d), 7.84(1H, dd), 8.15(1H,brs), 8.18(1H, d), 8.20(1H, brs), 8.40(1H, d). 50 1-(2,2,2-tri-466(M+H)⁺ (DMSO-d₆)δ(ppm): 1.05(6H, s), 2.00-2.20(4H, fluoroacetyl)-2,464(M−H)⁻ m), 3.30-3.50(7H, m), 3.60-3.70(1H, m), 3-dihydro-1H- 4.36(2H,t), 4.76-4.77(1H, m), 7.83(1H, d), indol-5-yl 7.87(1H, brs), 8.11(1H,d), 8.21(1H, t). 51 benzothiazol-6-yl 386(M+H)⁺ (DMSO-d₆)δ(ppm):1.37(6H, s), 2.08-2.26(4H, 384(M−H)⁻ m), 3.36-3.38(2H, m), 3.71-3.73(2H,m), 4.12-4.18(2H, m), 4.84(1H, dd), 8.09(1H, dd), 8.19(1H, d), 8.76(1H,s), 8.93(2H, brs), 9.55(1H, s). 52 4-methoxy-2- 430(M+H)⁺(DMSO-d₆)δ(ppm): 1.35(6H, s), 1.90-2.24(4H, methylbenzothiazol-428(M−H)⁻ m), 2.81(3H, s), 3.49-3.60(4H, m), 4.01(3H, 6-yl s),4.09-4.18(2H, m), 4.87(1H, dd), 7.54(1H, d), 8.19(1H, d), 8.90(1H, t),8.93(2H, brs).

TABLE 17 Example A ESI/MS(m/z) ¹H NMR 53 4-methoxy-2-tri- 484(M+H)⁺(DMSO-d₆)δ(ppm): 1.37(6H, s), 2.02-2.32(4H, fluoromethylbenzothiazol-482(M−H)⁻ m), 3.37-3.58(3H, m), 3.61(2H, d), 6-yl 3.66-3.77(1H, m),4.09(3H, s), 4.14-4.27(2H, m), 4.87(1H, d), 7.72(1H, s), 8.44(1H, s),8.96(2H, brs), 9.09(1H, t). 54 4-methoxy-2- 492(M+H)⁺ (DMSO-d₆)δ(ppm):1.38(6H, s), 2.01-2.26(4H, phenylbenzothiazol- 490(M−H)⁻ m),3.50-3.58(3H, m), 3.62(2H, d), 6-yl 3.74-3.79(1H, m), 4.09(3H, s),4.12-4.26(2H, m), 4.87(1H, dd), 7.60(3H, m), 7.64(1H, d), 8.11(2H, m),8.33(1H, d), 9.02(2H, brs), 9.05(1H, t). 55 2-oxo-2,3-dihydro- 402(M+H)⁺(DMSO-d₆)δ(ppm): 1.18(6H, s), 2.18-2.35(4H, benzothiazol-6-yl 400(M−H)⁻m), 3.35(2H, d), 3.41-3.51(1H, m), 3.46(2H, d), 3.62-3.69(1H, m),4.77(1H, dd), 7.08(1H, d), 7.37(1H, t), 7.71(1H, dd), 7.92(1H, d). 561-methyl-1H-benz- 383(M+H)⁺ (DMSO-d₆)δ(ppm): 1.36(6H, s), 1.95-2.30(4H,imidazol-5-yl 381(M−H)⁻ m), 3.50-3.65(2H, m), 3.65-3.75(2H, m), 4.03(3H,s), 4.05-4.25(2H, m), 4.87(1H, q), 7.96(1H, d), 8.09(1H, d), 8.42(1H,s), 8.85-9.10(2H, brs), 9.34(1H, brs). 57 2-methylbenz- 384(M+H)⁺(DMSO-d₆)δ(ppm): 1.34(6H, s), 1.95-2.30(4H, oxazol-6-yl 382(M−H)⁻ m),2.66(3H, s), 3.30-3.60(5H, m), 3.65 · .75(1H, m), 4.00-4.20(1H, m),4.86(1H, q), 7.76(1H, d), 7.92(1H, dd), 8.19(1H, d), 8.74(1H, t),8.75-8.90(1H, m). 58 isoquinolin-3-yl 380(M+H)⁺ (DMSO-d₆)δ(ppm):1.37(6H, s), 2.08-2.23(4H, 378(M−H)⁻ m), 3.30-3.80(4H, m), 4.10-4.80(2H,m), 4.86-4.87(1H, m), 7.85(1H, dd), 7.92(1H, dd), 8.30(1H, d), 8.23(1H,d), 8.65(1H, s), 9.00(2H, m), 9.30(1H, m), 9.46(1H, s). 59 indan-2-yl369(M+H)⁺ (DMSO-d₆)δ(ppm): 1.27(6H, s), 1.95-2.25(4H, 367(M−H)⁻ m),3.00-3.20(4H, m), 3.26(1H, q), 3.30-3.45(2H, m), 3.52(1H, q),3.65-3.75(1H, m), 4.00-4.20(2H, m), 4.86(1H, q), 7.10-7.25(4H, m),8.33(1H, brs), 8.90(2H, brs).

EXAMPLE 60

(S)-2-Methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid{2-[2(2-cyanopyrrolidin-1-yl)-2-oxoethylamino]-2-methylpropyl}methylamide

In a similar procedure as employed in the Example 1, the title compound(210 mg, Y.:28%) was obtained from2-methylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid (354 mg) and(S)-1-[2-(1,1-dimethyl-2-methylaminoethylamino)acetyl]pyrrolidine-2-carbonitrile(450 mg).

¹HNMR; (DMSO-d₆) δ (ppm):1.36 (6H, s), 1.98 (1H, brs),2.00-2.30 (4H, m),2.50 (3H, s), 2.90 (3H, s), 3.30-3.80 (4H, m), 4.10-4.30 (2H, m), 4.80(1H, m), 6.63 (1H, s), 8.80 (1H, s), 9.50 (1H, s).

ESI/MS (m/z):398 (M+H)⁺, 396 (M−H)⁻.

EXAMPLE 61

(S)-1-{2-[3-(1,3-Dihydroisoindol-2-yl)-1,1-dimethyl-3-oxopropylamino]acetyl}pyrrolidine-2-carbonitrile

Potassium carbonate (370 mg) and sodium iodide (200 mg) were added to asolution of 3-amino-1-(1,3-dihydroisoindol-2-yl)-3-methylbutan-1-one(0.55 g) in acetone.

(S)-1-(2′-Chloroacetyl)pyrrolidine-2-carbonitrile (467 mg) was addedthereto with ice cooling, and the mixture was stirred for 8 hours atroom temperature. Dichloromethane was added thereto, then insolublematter was removed by filtration, and the filtrate was concentratedunder reduced pressure. The residue was purified by columnchromatography (eluting solvent; dichloromethane:methanol 20:1) to givethe title compound (0.54 g, 61%).

¹H NMR; (DMSO-d₆) δ (ppm):1.39, 1.40 (6H, 2s), 2.00-2.25 (4H, m),2.85-2.95 (2H, m), 3.30-4.10 (4H, m), 4.71, 4.90 (4H, 2s), 4.85-4.90(1H, m), 7.30-7.40 (4H, m).

ESI/MS (m/z):355 (M+H)⁺.

In a similar procedure as employed in the Example 61, compounds weresynthesized according to the following reaction scheme. The synthesizedcompounds and data are shown in Tables 18 to 22. (Each symbol has thesame meaning as defined above.)

TABLE 18 Example A D n R1 R2 R³ R⁴ E ESI/MS (m/z) 625-methyl-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 369 (M + H)⁺2-yl 63 5-fluoro-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 373(M + H)⁺ 2-yl 64 5-bromo-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂—435 (M + H)⁺ 2-yl 433 (M − H)⁻ 65 5-chloro-1,3-dihydroisoindol- —CO— 1Me Me H CN —CH₂CH₂— 391 (M + H)⁺ 2-yl 389 (M − H)⁻ 665-t-butyl-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 411 (M + H)⁺2-yl 67 4-fluoro-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 373(M + H)⁺ 2-yl 371 (M − H)⁻ 68 4-methyl-1,3-dihydroisoindol- —CO— 1 Me MeH CN —CH₂CH₂— 369 (M + H)⁺ 2-yl 367 (M − H)⁻ 694,7-dichloro-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 423 (M +H)⁺ 2-yl 70 4-hydroxy-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂—371 (M + H)⁺ 2-yl 369 (M − H)⁻ 71 5-hydroxymethyl-1,3-dihydroisoindol-—CO— 1 Me Me H CN —CH₂CH₂— 385 (M + H)⁺ 2-yl 725-trifluoromethyl-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 423(M + H)⁺ 2-yl 421 (M − H)⁻ 73 4,5,6,7-tetrachloro-1,3-dihydroisoindol-—CO— 1 Me Me H CN —CH₂CH₂— 491 (M + H)⁺ 2-yl 745,6-dichloro-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 423 (M +H)⁺ 2-yl 75 4-hydroxy-6-methyl-1,3-dihydroisoindol- —CO— 1 Me Me H CN—CH₂CH₂— 385 (M + H)⁺ 2-yl 76 4-methoxy-6-methyl-1,3-dihydroisoindol-—CO— 1 Me Me H CN —CH₂CH₂— 399 (M + H)⁺ 2-yl 775-methoxy-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 385 (M + H)⁺2-yl 78 4-methoxy-1,3-dihydroisoindol- —CO— 1 Me Me H CN —CH₂CH₂— 385(M + H)⁺ 2-yl

TABLE 19 Example A D n R1 R2 R³ R⁴ E ESI/MS (m/z) 793,4-dihydro-1H-isoquinolin-2-yl —CO— 1 Me Me H CN —CH₂CH₂— 369 (M + H)⁺367 (M − H)⁻ 80 1,3-dihydroisoindol-2-yl —CO— 0 Me Me H CN —CH₂CH₂— 341(M + H)⁺ 81 1,3,4,5-tetrahydrobenzo[c]azepin- —CO— 0 Me Me H CN —CH₂CH₂—369 (M + H)⁺ 2-yl 367 (M − H)⁻ 82 1,3-dihydroisoindol-2-yl- —CO— 2 Me MeH CN —CH₂CH₂— 369 (M + H)⁺ 367 (M − H)⁻ 832-methylpyrazolo[1,5-a]pyrimidin- —CONH— 1 Me Me H (R) CN —CH₂CH₂— 384(M + H)⁺ 6-yl 382 (M − H)⁻ 84 2-methylpyrazolo[1,5-a]pyrimidin- —CONH— 1Me Me H CN —SCH₂— 402 (M + H)⁺ 6-yl 400 (M − H)⁻ 852-methylpyrazolo[1,5-a]pyrimidin- —CONH— 1 Me Me H CN —CH₂— 370 (M + H)⁺6-yl 368 (M − H)⁻ 86 2-methylpyrazolo[1,5-a]pyrimidin- —CONH— 1cyclopentyl H CN —CH₂CH₂— 410 (M + H)⁺ 6-yl 408 (M − H)⁻ 872-methylpyrazolo[1,5-a]pyrimidin- —CONH— 3 Me Me H CN —CH₂CH₂— 412 (M +H)⁺ 6-yl 410 (M − H)⁻ 88 benzothiazol-6-yl —CONH— 1 H —COOMe H CN—CH₂CH₂— 416 (M + H)⁺ 414 (M − H)⁻ 89 1,3-dihydroisoindol-2-yl —CO— 1 HH H CN —CH₂CH₂— 327 (M + H)⁺ 90 3,4-dihydro-1H-isoquinolin-2-yl —CO— 1 HH H CN —CH₂CH₂— 341 (M + H)⁺ 91 2,3-dihydroindol-1-yl —CO— 1 H H H CN—CH₂CH₂— 327 (M + H)⁺ 325 (M − H)⁻ 94 indol-1-yl —CO— 1 H H H CN—CH₂CH₂— 325 (M + H)⁺ 323 (M − H)⁻ 92 1,3-dihydroisoindol-2-yl —CO— 2 HH H CN —CH₂CH₂— 341 (M + H)⁺ 93 benzothiazol-2-yl —NHCO— 1 H H H CN—CH₂CH₂— 358 (M + H)⁺ 356 (M − H)⁻ 95 benzothiazol-6-yl —CONH— 1 H H HCN —CH₂CH₂— 358 (M + H)⁺ 96 benzothiazol-6-yl —CONH— 1 H H Ph CN—CH₂CH₂— 435 (M + H)⁺ 97 benzothiazol-6-yl —CONH— 1 H H H H —SCH₂— 351(M + H)⁺

TABLE 20 Example A D n R1 R2 R³ R⁴ E ESI/MS (m/z) 98 benzothiazol-6-yl—CONH— 1 H H H H —CH₂CH₂— 333 (M + H)⁺ 99 benzothiazol-6-yl —CONH— 1 H HH CN —CH₂CH₂CH₂— 372 (M + H)⁺ 100 benzothiazol-6-yl —CONH— 1 H H H H—CH₂OCH₂— 349 (M + H)⁺ 101 2-methylbenzothiazol-6-yl —CONH— 1 H H H CN—CH₂CH₂— 372 (M + H)⁺ 102 5-methoxybenzothiazol-6-yl —CONH— 1 H H H CN—CH₂CH₂— 388 (M + H)⁺ 386 (M − H)⁻ 103 4-methoxybenzothiazol-6-yl —CONH—1 H H H CN —CH₂CH₂— 388 (M + H)⁺ 104 2-phenylbenzothiazol-6-yl —CONH— 1H H H CN —CH₂CH₂— 435 (M + H)⁺ 105 benzothiazol-6-yl —CONH— 3 H H H CN—CH₂CH₂— 386 (M + H)⁺ 106 1-methyl-1H-indol-2-yl —CONH— 1 H H H CN—CH₂CH₂— 354 (M + H)⁺ 107 isoquinolin-3-yl —CONH— 1 H H H CN —CH₂CH₂—352 (M + H)⁺ 108 isoquinolin-3-yl —CONH— 1 H H H H —SCH₂— 345 (M + H)⁺109 isoquinolin-3-yl —CONH— 1 H H H H —CH₂CH₂— 327 (M + H)⁺ 110isoquinolin-3-yl —CONH— 1 H H H CN —CH₂CH₂CH₂— 366 (M + H)⁺ 111isoquinolin-3-yl —CONH— 1 H H H H —CH₂OCH₂— 343 (M + H)⁺ 112isoquinolin-1-yl —CONH— 1 H H H CN —CH₂CH₂— 352 (M + H)⁺ 113isoquinolin-1-yl —CONH— 1 H H H H —SCH₂— 345 (M + H)⁺ 114isoquinolin-1-yl —CONH— 1 H H H H —CH₂CH₂— 327 (M + H)⁺ 115isoquinolin-1-yl —CONH— 1 H H H H —CH₂OCH₂— 343 (M + H)⁺ 116quinolin-3-yl —CONH— 1 H H H CN —CH₂CH₂— 352 (M + H)⁺

TABLE 21 Example A D n R1 R2 R³ R⁴ E ESI/MS (m/z) 117 quinolin-3-yl—CONH— 1 H H H H —SCH₂— 345 (M + H)⁺ 118 quinolin-3-yl —CONH— 1 H H H H—CH₂CH₂— 327 (M + H)⁺ 119 quinolin-3-yl —CONH— 1 H H H CN —CH₂CH₂CH₂—366 (M + H)⁺ 120 quinolin-3-yl —CONH— 1 H H H H —CH₂OCH₂— 343 (M + H)⁺121 quinolin-2-yl —CONH— 1 H H H CN —CH₂CH₂— 352 (M + H)⁺ 1221,3-dimethyl-1H-pyrazolo[3,4- —CONH— 1 H H H CN —CH₂CH₂— 370 (M + H)⁺b]pyridin-5-yl 123 1,3-dimethyl-1H-pyrazolo[3,4- —CONH— 1 H H H H —SCH₂—363 (M + H)⁺ b]pyridin-5-yl 124 1,3-dimethyl-1H-pyrazolo[3,4- —CONH— 1 HH H H —CH₂CH₂— 345 (M + H)⁺ b]pyridin-5-yl 1251,3-dimethyl-1H-pyrazolo[3,4- —CONH— 1 H H H H —CH₂OCH₂— 361 (M + H)⁺b]pyridin-5-yl 126 5-oxo-2,3-dihydro-5H-thiazolo —CONH— 1 H H H CN—CH₂CH₂— 377 (M + H)⁺ [3,2-a]pyrimidin-6-yl 127 5-oxo-2,3-dihydro-5H-—CONH— 1 H H H H —SCH₂— 370 (M + H)⁺ thiazolo[3,2-a]pyrimidin-6-yl 1285-oxo-2,3-dihydro-5H-thiazolo —CONH— 1 H H H H —CH₂CH₂— 352 (M + H)⁺[3,2-a]pyrimidin-6-yl 129 5-oxo-2,3-dihydro-5H-thiazolo —CONH— 1 H H HCN —CH₂CH₂CH₂— 391 (M + H)⁺ [3,2-a]pyrimidin-6-yl 1305-oxo-2,3-dihydro-5H-thiazolo —CONH— 1 H H H H —CH₂OCH₂— 368 (M + H)⁺[3,2-a]pyrimidin-6-yl 131 2,7-dimethylpyrazolo[1,5-a]- —CONH— 1 H H H CN—CH₂CH₂— 370 (M + H)⁺ pyrimidin-6-yl 132 2,7-dimethylpyrazolo[1,5-a]-—CONH— 1 H H H H —SCH₂— 363 (M + H)⁺ pyrimidin-6-yl 1332,3-dihydrobenzo[1,4]dioxan- —CONH— 1 H H H CN —CH₂CH₂— 359 (M + H)⁺6-yl 134 2,3-dihydrobenzo[1,4]dioxan- —CONH— 1 H H H H —SCH₂— 352 (M +H)⁺ 6-yl 135 2-methylimidazo[1,2-a]- —CONH— 1 H H H CN —CH₂CH₂— 355 (M +H)⁺ pyridin-3-yl

TABLE 22 Example A D n R1 R2 R³ R⁴ E ESI/MS (m/z) 1362-methylimidazo[1,2-a]- —CONH— 1 H H H H —SCH₂— 348 (M + H)⁺pyridin-3-yl 137 2-methylimidazo[1,2-a]- —CONH— 1 H H H H —CH₂CH₂— 330(M + H)⁺ pyridin-3-yl 138 2-methylimidazo[1,2-a]- —CONH— 1 H H H H—CH₂OCH₂— 346 (M + H)⁺ pyridin-3-yl 139 8-ethyl-5-oxo-2-pyrrolidin-1-—CONH— 1 H H H CN —CH₂CH₂— 468 (M + H)⁺ yl-5,8-dihydropyrido[2,3-d]-pyrimidin-6-yl 140 8-ethyl-5-oxo-2-pyrrolidin-1- —CONH— 1 H H H H —SCH₂—461 (M + H)⁺ yl-5,8-dihydropyrido[2,3-d]- pyrimidin-6-yl 1418-ethyl-5-oxo-2-pyrrolidin-1- —CONH— 1 H H H CN —CH₂CH₂CH₂— 482 (M + H)⁺yl-5,8-dihydropyrido[2,3-d]- pyrimidin-6-yl

EXAMPLE 142

(S)-1-{2-[2-(1,3-Dihydroisoindol-2-yl)-2-oxoethylamino]acetyl}pyrrolidine-2-carbonitrile

{t-Butoxycarbonyl-[2-(1,3-dihydroisoindol-2-yl)-2-oxoethyl]amino}aceticacid (260 mg), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimidehydrochloride (150 mg) and hydroxybenzotriazole (120 mg) were dissolvedin N,N-dimethylformamide (5.0 ml). Triethylamine (110 μl) and(S)-pyrrolidine-2-carbonitrile hydrochloride (100 mg) were addedthereto, and the mixture was stirred for 21 hours at room temperature.The reaction mixture was concentrated under reduced pressure, then ethylacetate and 10% citric acid solution were added to the residue, and theorganic phase was separated. The organic phase was washed with 4% sodiumbicarbonate solution and a saturated saline solution and dried oversodium sulfate anhydrous. The reaction mixture was concentrated underreduced pressure, and the residue was purified by column chromatography(eluting solvent; dichloromethane:methanol 20:1) to give t-butyl(S)-[2-(cyanopyrrolidin-1-yl)-2-oxoethyl]-[2-(1,3-dihydroisoindol-2-yl)-2-oxoethyl]carbamate (290 mg, Y.:90%).

ESI/MS (m/z):413 (M+H)⁺, 411 (M−H)⁻.

The t-butyl (S)-[2-(cyanopyrrolidin-1-yl)-2-oxoethyl]-[2-(1,3-dihydroisoindol-2-yl)-2-oxoethyl]carbamate (280 mg) obtained above was dissolvedin 1,4-dioxane (1.0 ml), and 4 N Hydrochloric acid/1,4-dioxane (1.0 ml)was added thereto and stirred for 30 minutes with ice cooling. Ether wasadded thereto, and precipitated crystals were collected by filtrationand dried under reduced pressure to give a hydrochloride (240 mg, Y.:quant.) of the title compound.

¹H NMR; (DMSO-d₆) δ (ppm):2.03-2.19 (4H, m), 3.36-3.44 (2H, m), 3.57,4.10 (4H, 2s), 4.74, 4.84 (4H, 2s), 4.86-4.88 (1H, m), 7.32-7.39 (4H,m).

ESI/MS (m/z):313 (M+H)⁺, 311 (M−H)⁻.

In a similar procedure as employed in the Example 142, compounds weresynthesized according to the following reaction scheme. The synthesizedcompounds and data are shown in Tables 23 to 27.

TABLE 23 Example A D R⁴ E ESI/MS (m/z) 143 1,3-dihydroisoindol-2-yl —CO—H —SCH₂— 306 (M + H)⁺ 144 1,3-dihydroisoindol-2-yl —CO— H —CH₂CH₂— 288(M + H)⁺ 145 1,3-dihydroisoindol-2-yl —CO— (±)CN —CH₂CH₂CH₂— 327 (M +H)⁺

TABLE 24 Example A D R⁴ E ESI/MS (m/z) 146 1,3-dihydroisoindol-2-yl —CO—H —CH₂OCH₂— 304 (M + H)⁺ 147 1,3-dihydroisoindol-2-yl —CO— H —CH₂CH₂CH₂—302 (M + H)⁺ 148 2,3-dihydroindol-1-yl —CO— CN —CH₂CH₂— 313 (M + H)⁺ 1492,3-dihydroindol-1-yl —CO— H —SCH₂— 306 (M + H)⁺ 1502,3-dihydroindol-1-yl —CO— H —CH₂CH₂— 288 (M + H)⁺ 1512,3-dihydroindol-1-yl —CO— (±)CN —CH₂CH₂CH₂— 327 (M + H)⁺ 1522,3-dihydroindol-1-yl —CO— H —CH₂OCH₂— 304 (M + H)⁺ 1532,3-dihydroindol-1-yl —CO— H —CH₂CH₂CH₂— 302 (M + H)⁺ 1543,4-dihydro-1H-isoquinolin-2-yl —CO— CN —CH₂CH₂— 327 (M + H)⁺ 1553,4-dihydro-1H-isoquinolin-2-yl —CO— H —SCH₂— 320 (M + H)⁺ 1563,4-dihydro-1H-isoquinolin-2-yl —CO— H —CH₂CH₂— 302 (M + H)⁺ 1573,4-dihydro-1H-isoquinolin-2-yl —CO— (±)CN —CH₂CH₂CH₂— 341 (M + H)⁺ 1583,4-dihydro-1H-isoquinolin-2-yl —CO— H —CH₂OCH₂— 318 (M + H)⁺ 1593,4-dihydro-1H-isoquinolin-2-yl —CO— H —CH₂CH₂CH₂— 326 (M + H)⁺ 1603,4-dihydro-2H-quinolin-1-yl —CO— CN —CH₂CH₂— 327 (M + H)⁺ 1613,4-dihydro-2H-quinolin-1-yl —CO— H —SCH₂— 320 (M + H)⁺ 1623,4-dihydro-2H-quinolin-1-yl —CO— H —CH₂CH₂— 302 (M + H)⁺ 1633,4-dihydro-2H-quinolin-1-yl —CO— (±)CN —CH₂CH₂CH₂— 341 (M + H)⁺

TABLE 25 Example A D R⁴ E ESI/MS (m/z) 164 3,4-dihydro-2H-quinolin-1-yl—CO— H —CH₂OCH₂— 318 (M + H)⁺ 165 3,4-dihydro-2H-quinolin-1-yl —CO— H—CH₂CH₂CH₂— 326 (M + H)⁺ 166 isoquinolin-3-yl —NHCO— CN —CH₂CH₂— 338(M + H)⁺ 336 (M − H)⁻ 167 isoquinolin-3-yl —NHCO— H —SCH₂— 331 (M + H)⁺168 isoquinolin-3-yl —NHCO— H —CH₂CH₂— 313 (M + H)⁺ 169 isoquinolin-3-yl—NHCO— (±)CN —CH₂CH₂CH₂— 352 (M + H)⁺ 170 isoquinolin-3-yl —NHCO— H—CH₂OCH₂— 329 (M + H)⁺ 171 isoquinolin-3-yl —NHCO— H —CH₂CH₂CH₂— 327(M + H)⁺ 172 quinolin-2-yl —NHCO— CN —CH₂CH₂— 338 (M + H)⁺ 336 (M − H)⁻173 quinolin-2-yl —NHCO— H —SCH₂— 331 (M + H)⁺ 174 quinolin-2-yl —NHCO—H —CH₂CH₂— 313 (M + H)⁺ 175 quinolin-2-yl —NHCO— (±)CN —CH₂CH₂CH₂— 352(M + H)⁺ 176 quinolin-2-yl —NHCO— H —CH₂OCH₂— 329 (M + H)⁺ 177quinolin-2-yl —NHCO— H —CH₂CH₂CH₂— 327 (M + H)⁺ 1782-methylquinolin-4-yl —NHCO— CN —CH₂CH₂— 352 (M + H)⁺ 1792-methylquinolin-4-yl —NHCO— H —SCH₂— 345 (M + H)⁺ 1802-methylquinolin-4-yl —NHCO— H —CH₂CH₂— 327 (M + H)⁺ 1812-methylquinolin-4-yl —NHCO— (±)CN —CH₂CH₂CH₂— 366 (M + H)⁺

TABLE 26 Example A D R⁴ E ESI/MS (m/z) 182 2-methylquinolin-4-yl —NHCO—H —CH₂CH₂CH₂— 341 (M + H)⁺ 183 3-methylquinolin-5-yl —NHCO— CN —CH₂CH₂—353 (M + H)⁺ 184 3-methylquinolin-5-yl —NHCO— H —SCH₂— 346 (M + H)⁺ 1853-methylquinolin-5-yl —NHCO— H —CH₂CH₂— 328 (M + H)⁺ 1863-methylquinolin-5-yl —NHCO— (±)CN —CH₂CH₂CH₂— 367 (M + H)⁺ 1873-methylquinolin-5-yl —NHCO— H —CH₂OCH₂— 344 (M + H)⁺ 1883-methylquinolin-5-yl —NHCO— H —CH₂CH₂CH₂— 342 (M + H)⁺ 1894-methyl-2-oxo-2H-chromen-7-yl —NHCO— CN —CH₂CH₂— 369 (M + H)⁺ 367 (M −H)⁻ 190 4-methyl-2-oxo-2H-chromen-7-yl —NHCO— H —SCH₂— 362 (M + H)⁺ 1914-methyl-2-oxo-2H-chromen-7-yl —NHCO— H —CH₂CH₂— 344 (M + H)⁺ 1924-methyl-2-oxo-2H-chromen-7-yl —NHCO— (±)CN —CH₂CH₂CH₂— 383 (M + H)⁺ 1934-methyl-2-oxo-2H-chromen-7-yl —NHCO— H —CH₂OCH₂— 360 (M + H)⁺ 1944-methyl-2-oxo-2H-chromen-7-yl —NHCO— H —CH₂CH₂CH₂— 358 (M + H)⁺ 195benzothiazol-2-yl —NHCO— CN —CH₂CH₂— 344 (M + H)⁺ 196 benzothiazol-2-yl—NHCO— H —SCH₂— 337 (M + H)⁺ 197 benzothiazol-2-yl —NHCO— H —CH₂CH₂— 319(M + H)⁺ 198 benzothiazol-2-yl —NHCO— (±)CN —CH₂CH₂CH₂— 358 (M + H)⁺ 199benzothiazol-2-yl —NHCO— H —CH₂CH₂CH₂— 333 (M + H)⁺

TABLE 27 Example A D R⁴ E ESI/MS (m/z) 200 9H-purin-6-yl —NHCO— CN—CH₂CH₂— 329 (M + H)⁺ 201 9H-purin-6-yl —NHCO— H —SCH₂— 322 (M + H)⁺ 2029H-purin-6-yl —NHCO— H —CH₂CH₂— 304 (M + H)⁺ 203 9H-purin-6-yl —NHCO—(±)CN —CH₂CH₂CH₂— 343 (M + H)⁺ 204 9H-purin-6-yl —NHCO— H —CH₂CH₂CH₂—318 (M + H)⁺ 205 2-methylsulfanyl[1,2,4]triazolo[1,5- —NHCO— CN —CH₂CH₂—375 (M + H)⁺ a]pyrimidin-7-yl 206 2-methylsulfanyl[1,2,4]triazolo[1,5-—NHCO— H —SCH₂— 368 (M + H)⁺ a]pyrimidin-7-yl 2072-methylsulfanyl[1,2,4]triazolo[1,5- —NHCO— H —CH₂CH₂— 350 (M + H)⁺a]pyrimidin-7-yl 208 2-methylsulfanyl[1,2,4]triazolo[1,5- —NHCO— (±)CN—CH₂CH₂CH₂— 389 (M + H)⁺ a]pyrimidin-7-yl 2092-methylsulfanyl[1,2,4]triazolo[1,5- —NHCO— H —CH₂CH₂CH₂— 364 (M + H)⁺a]pyrimidin-7-yl 210 octahydroquinolin-1-yl —CO— CN —CH₂CH₂— 333 (M +H)⁺

PHARMACOLOGICAL TEST EXAMPLE 1

In screening of DPP-IV inhibitor, the following method usingglycyl-proline-4-methylcumalyl-7-amide (Gly-Pro-MCA) as substrate wasused.

A test substance (40 μl) in various concentrations dissolved in ameasurement buffer (Tris-HCl buffer (25 mM), pH 7.4, containing sodiumchloride (140 mM), calcium chloride (10 nM), 1% bovine serum albumin),and 150 μM Gly-Pro-MCA substrate (40 μl), were put into each well of a96-well microtiter plate, then mixed and left at room temperature for 5minutes. There after, human plasma (20 μl) diluted30-fold with themeasurement buffer was added to each well, stirred and reacted at roomtemperature for 30 minutes in the dark. The reaction was terminated byadding 100 μl of 1 M acetate buffer, pH 4.2, and MCA released by theactivity of DPP-IV was determined by measuring fluorescence at 465 nmobtained by excitation at 360 nm. The concentration (IC₅₀) at which 50%of the activity of DPP-IV was inhibited by the test substance wasdetermined on the basis of the activity of DPP-IV calculated accordingto the following equation. The results are shown in Table 28. Isoleucylthiazolidide (Compound A) described in a patent (WO97/40832) was used ascomparative chemical.

Inhibitory activity on DPP-IV=100×(1−(Fs−Fb)/F100−Fb) F100:fluorescenceintensity obtained by reaction with plasma. Fb:fluorescence intensity ofa blank where the reaction was carried out with the reaction terminatingsolution added. Fs:fluorescence intensity obtained by adding the testsubstance.

TABLE 28 Compound DPP-IV (Example No.) IC50 (μM)  1 0.051  2 0.032  30.023  4 0.087  6 0.091  8 0.054  9 0.061  10 0.085  11 0.068  12 0.028 13 0.024  15 0.028  16 0.033  18 0.036  19 0.050  20 0.052  21 0.028 22 0.073  23 0.082  24 0.043  25 0.048  26 0.033  27 0.021  28 0.078 30 0.089  31 0.049  32 0.048  33 0.071  34 0.023  35 0.037  36 0.045 37 0.017  38 0.025  39 0.073  41 0.025  42 0.027  43 0.016  44 0.037 45 0.028  46 0.019  47 0.024  48 0.031  49 0.020  50 0.020  51 0.026 53 0.048  55 0.024  56 0.030  57 0.035  59 0.050  61 0.010  62 0.027 63 0.018  64 0.024  65 0.011  66 0.050  67 0.007  68 0.016  69 0.021 70 0.032  71 0.002  72 0.039  73 0.094  74 0.044  75 0.014  76 0.022 77 0.022  78 0.015  82 0.017  89 0.025  91 0.082  92 0.052  93 0.062 95 0.013 101 0.066 102 0.090 105 0.031 122 0.026 126 0.031 Compound A0.225

From the results of this test, the compound of the present inventionshowed an IC₅₀ value of tens nM, and was found to have a strongerinhibitory activity on DPP-IV than Compound A (the IC₅₀:225 nM).

PHARMACOLOGICAL TEST EXAMPLE 2

Wistar/ST male rats (Japan SLC, Inc.) were acclimated for 5 days or more(8-week-old when used) and then fasted overnight. The compound (3 mg/kg)in Example 1, the compound (1 mg/kg) in Example 61 and Compound A (10mg/kg) were orally administered in a volume of 5 ml/kg into ratsrespectively, and after 30 minutes, 20% glucose solution (5 ml/kg)(corresponding to glucose (1 g/kg).) was orally administered to eachrat. From the tip end of each tail, blood was collected with time, andplasma was separated, and blood glucose and insulin levels weremeasured. The blood level was measured by using Glutest (Sanwa KagakuKenkyusho Co., Ltd.), and the plasma insulin level was measured by usinga commercially available EAI kit (Shibayagi Co., Ltd.).

The results are shown in Table 29. The blood glucose level was expressedin terms of area-under-curve (AUC_(0-60 min)) (min·mg/dl) from 0 min.after sugar administration to 60 minutes, wherein the blood glucoselevel in a sample obtained by blood collection before the test wassubstituted for the blood glucose level at 0 min. The plasma insulinlevel was indicated by the plasma insulin level (pg/ml) 10 minutes afteradministration of the compound.

TABLE 29 Administration Blood glucose level Insulin Administration Bloodglucose level Insulin group (min · mg/dl) (pg/ml) group (min · mg/dl)(pg/ml) Water 8199 ± 235 1692 ± 583 Water 8208 ± 368 2008 ± 666 CompoundA 6671 ± 161 2994 ± 310 Compound A 6769 ± 128 3670 ± 827 Example 1 7024± 222 2745 ± 574 Example 61 7055 ± 287  4093 ± 1050

From the results of this test, it was found that the compound of thepresent invention exhibits a blood glucose depressant action based onits insulin secretion potentiation.

As described above, the compound of the present invention is a compoundwhich exhibits a potent inhibitory activity on DPP-IV, is chemicallystable, is excellent in enzyme selectivity without side effects and thelike, and is thus useful in treatment of diabetes (particularly type 2diabetes), its related complications, obesity and the like.

1. A compound represented by the general formula (I):

wherein R¹ and R² are the same or different and each represents ahydrogen atom, an optionally substituted C1-6 alkyl group, or —COOR⁵whereupon R⁵ represents a hydrogen atom or an optionally substitutedC1-6 alkyl group, or R¹ and R², together with a carbon atom to whichthey are bound, represent a 3- to 6-membered cycloalkyl group, R³represents a hydrogen atom or an optionally substituted C6-10 arylgroup, R⁴ represents a hydrogen atom or a cyano group, D represents—CONR⁶—, —CO— or —NR⁶CO—, R⁶ represents a hydrogen atom or an optionallysubstituted C1-6 alkyl group, E represents —(CH₂)₂— or —SCH₂—, n is aninteger of 0 to 3, and A represents an optionally substituted 6-5-systembicyclic heterocyclic group containing nitrogen in the 5-membered ringof the bicyclic heterocyclic group.
 2. The compound according to claim1, wherein in the general formula (I), each of R¹ and R² is a methylgroup, R³ is a hydrogen atom, R⁴ is a cyano group, D is —CONH— or —CO—,E is —CH₂CH₂—, and n is 1 or
 2. 3. The compound according to claim 2,wherein in the general formula (I), D is —CO—, and A is a 6-5-systembicyclic alicyclic heterocyclic group represented by the followingformula:

wherein x is an integer of 0 to 2, R⁷, R⁸, R⁹ and R¹⁰ are the same ordifferent and each represents a hydrogen atom, a halogen atom, a hydroxygroup, a trifluoromethyl group, an optionally substituted C1-6 alkylgroup or an optionally substituted C1-6 alkoxy group.
 4. The compoundaccording to claim 2, wherein in the general formula (I), D is —CONH—,and A is a 6-5-system bicyclic heterocyclic group represented by thefollowing formula:

wherein

represents a single or double bond, at least one of y, z, v and w is anoxygen, nitrogen or sulfur atom, R¹¹, R¹² and R¹³ may be substituted onany hydrogen atoms on the ring, are the same or different and eachrepresents a hydrogen atom, a hydroxy group, a trifluoromethyl group, atrifluoroacetyl group, an oxo group, an optionally substituted C1-6alkyl group, an optionally substituted C1-6 alkoxy group, or anoptionally substituted C6-10 aryl group.
 5. The compound according toclaim 4, wherein 1 to 3 groups out of y, z, v and w in the formula (III)are nitrogen atoms, and the remainder is a carbon atom.
 6. The compoundaccording to claim 4, wherein y in the formula (III) is nitrogen atomand each of w, x and z is a carbon atom.
 7. The compound according toclaim 4, wherein v, w and y in the formula (III) are nitrogen atoms andz is a carbon atom.
 8. A pharmaceutical composition comprising as anactive ingredient a compound represented by the general formula (I):

wherein R¹ and R² are the same or different and each represents ahydrogen atom, an optionally substituted C1-6 alkyl group, or —COOR⁵whereupon R⁵ represents a hydrogen atom or an optionally substitutedC1-6 alkyl group, or R¹ and R², together with a carbon atom to whichthey are bound, represent a 3- to 6-membered cycloalkyl group, R³represents a hydrogen atom or an optionally substituted C6-10 arylgroup, R⁴represents a hydrogen atom or a cyano group, D represents—CONR⁶—, —CO— or —NR⁶CO—, R⁶ represents a hydrogen atom or an optionallysubstituted C1-6 alkyl group, E represents —(CH₂)₂— or —SCH₂—, n is aninteger of 0 to 3, and A represents an optionally substituted 6-5-systembicyclic heterocyclic group containing nitrogen in the 5-membered ringof the bicyclic heterocyclic group.
 9. The pharmaceutical compositionaccording to claim 8, wherein in the general formula (I), each of R¹ andR² is a methyl group, R³ is a hydrogen atom, R⁴ is a cyano group, D is—CONH— or —CO—, E is —CH₂CH₂—, and n is 1 or
 2. 10. The pharmaceuticalcomposition according to claim 9, wherein in the general formula (I), Dis —CO—, and A is a 6-5-system bicyclic alicyclic heterocyclic grouprepresented by the following formula:

wherein x is an integer of 0 to 2, R⁷, R⁸, R⁹ and R¹⁰ are the same ordifferent and each represents a hydrogen atom, a halogen atom, a hydroxygroup, a trifluoromethyl group, an optionally substituted C1-6 alkylgroup or an optionally substituted C1-6 alkoxy group.
 11. Thepharmaceutical composition according to claim 9, wherein in the generalformula (I), D is —CONH—, and A is a 6-5-system bicyclic heterocyclicgroup represented by the following formula:

wherein

represents a single or double bond, at least one of y, z, v and w is anoxygen, nitrogen or sulfur atom, R¹¹, R¹² and R¹³ may be substituted onany hydrogen atoms on the ring, are the same or different and eachrepresents a hydrogen atom, a hydroxy group, a trifluoromethyl group, atrifluoroacetyl group, an oxo group, an optionally substituted C1-6alkyl group, an optionally substituted C1-6 alkoxy group, or anoptionally substituted C6-10aryl group.
 12. The pharmaceuticalcomposition according to claim 11, wherein 1 to 3 groups out of y, z, vand w in the formula (III) are nitrogen atoms, and the remainder is acarbon atom.
 13. The pharmaceutical composition according to claim 11,wherein y in the formula (III) is a nitrogen atom and each of w, x and zis a carbon atom.
 14. The pharmaceutical composition according to claim11, wherein v, w and y in the formula (III) are nitrogen atoms and z isa carbon atom.
 15. The pharmaceutical composition according to claim 8,which is for treatment of diabetes.